Reply
 
Thread Tools Display Modes
 
Old 07-05-2016, 08:09 PM   #1
Senior Member
 
Diesel Duck's Avatar
 
City: discomfort.reactants.peanuts
Country: Colombia, South America and Huatulco, Mexico
Join Date: Sep 2014
Posts: 452
Solar Panels and Shadows...

While surfing the internet I came across this Vlog featuring a couple equipping their new catamaran with solar panels and thought some of you might be interested in seeing their test results:

__________________
Advertisement

__________________
Diesel Duck
*For Sale or Trade this oceanfront Mexican villa (www.QuintaAlegria.com) for the right 'Trawler' - Nordhavn, Kadey Krogen, Diesel Duck or ???
Diesel Duck is offline   Reply With Quote
Old 07-06-2016, 10:54 AM   #2
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 1,577
Solar Panels and Shadows...

Thanks for that post DD. I'm hooked up in parallel. I get the most consistent performance under "cloudy-bright" skies.

Jim
Sent from my iPad using Trawler Forum
__________________

JDCAVE is offline   Reply With Quote
Old 07-06-2016, 02:09 PM   #3
Guru
 
READY2GO's Avatar
 
City: Marathon, Florida
Country: USA
Vessel Name: Walkabout
Vessel Model: 1989 Sea Ray 380 Aft Cabin
Join Date: Jan 2012
Posts: 521
Very interesting results with the shading tests. It seems blocking part of one or more cells cuts output by 40% to 50% but blocking even one whole cell cuts the output by as much as 90%. Good info to have.
__________________
"Whenever you find yourself on the side of the majority, it is time to pause and reflect." Mark Twain

www.mikeandsharondunsworth.blogspot.com
READY2GO is offline   Reply With Quote
Old 07-16-2016, 06:14 PM   #4
Guru
 
foggysail's Avatar
 
City: Ashland, MA
Country: United States
Vessel Model: 1990 Silverton 40 aftcabin
Join Date: Jul 2016
Posts: 569
Until this season, My 4 150 watt panels delivered just shy of 25 amperes for most of the day. This year my max is around 20. Now of course I never washed the panels but that is high on my list to do soon.

Others may have this same dirty problem
foggysail is offline   Reply With Quote
Old 07-16-2016, 08:22 PM   #5
TF Site Team
 
FlyWright's Avatar
 
City: California Delta and SF Bay
Country: Sacramento, CA, USA (boat in Vallejo)
Vessel Name: FlyWright
Vessel Model: Marshall Californian 34 LRC
Join Date: Apr 2008
Posts: 10,032
That would be a good test....before and after the washdown. Don't forget the pictures for comparison. We like pictures.
__________________
Al

Custom Google Trawler Forum Search
FlyWright is offline   Reply With Quote
Old 07-16-2016, 08:45 PM   #6
Guru
 
foggysail's Avatar
 
City: Ashland, MA
Country: United States
Vessel Model: 1990 Silverton 40 aftcabin
Join Date: Jul 2016
Posts: 569
I'll take pictures but there is a but! I long ago gave up trying post pictures in forums. Now this forum may be different but other forums want pictures from web sites only. That would mean I have to download to some yet to be determined site before posting.


I will post the results but the best I can offer is to email the pictures to somebody and let them post them

Back to solar! I set up an automatic transfer switch ( a relay in layman terms) to switch to a 2KW true sine wave inverter in the absence of AC from either dock or my genny power. My battery bank consists of 4 East Penn golf carts to make up two 12v banks which I connect in parallel. This provides 440 AH of battery.

I have an 8 cubic foot fridge on the boat with self defrost. We have 2 32" tvs plus lighting. And yes I also have a Xantrex 50 amp charger which for the most part only charges the generator battery.

The panels! Those things replace all the consumed battery power every day we are out unless its raining. I highly recommend solar for boats. Homes are another matter requiring much discussion.
foggysail is offline   Reply With Quote
Old 07-16-2016, 11:42 PM   #7
TF Site Team
 
Peter B's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Lotus
Vessel Model: Clipper (CHB) 34 Sedan/Europa style
Join Date: Jun 2008
Posts: 6,627
Send a message via Skype™ to Peter B
Quote:
Originally Posted by foggysail View Post
I'll take pictures but there is a but! I long ago gave up trying post pictures in forums. Now this forum may be different but other forums want pictures from web sites only. That would mean I have to download to some yet to be determined site before posting.
You don't have to do that foggysail. Although you can do that, and some keen types do, using dropbox iCloud or similar, and just clicking on the "add an image icon at the top of the input window. But...this forum software is very user friendly, and you can post multiple pics as long as they are not too huge, right off the computer you're working on.

Just make sure you're in 'advanced post' mode, not 'quick reply', which is automatic if you click on the reply button rather than just posting in the quick reply window, but even if you were, there is a button below it labelled 'go advanced', so that will take you to the advanced post window.

You then click on manage attachments, then click on 'choose file', which takes you via browse, to your computer so you can browse to your photos, then just click on the photos you want just repeating eh selecting process, then when you have the pics chosen, you click on 'upload', and (most important) WAIT, for the upload to complete by watching the blue line across the top or whatever your computer does while it is uploading. Then scroll down to the bottom and click on 'close this window', then select submit post from the bottom of the window where you pic files are listed, and bob'syeruncle...pics posted - 'piece of cake.'
__________________
Pete
Peter B is offline   Reply With Quote
Old 07-17-2016, 04:44 AM   #8
Senior Member
 
City: Hong Kong
Country: Hong Kong
Join Date: Nov 2012
Posts: 210
Parallel and Series connection

Excellent video, thanks...it got me thinking about my setup which is both in series and parallel...I am installing 4 x 230W, 41V semi flexible panels in a series/parallel configuration creating about 82V for the Mastervolt SCM60 MPPT-MB charger.

The 4 panels will be placed in a row (front to aft) along the top of the bimini, The mast is right behind the bimini so it creates some shading on the 2 panels closest to the mast...

There are several ways to connect these panels: number 1 + 4 in parallel and number 2+3 in parallel, then series connect them. Or parallel number 1+2 and 3+4, then series connect them...or parallel number 1+3 and 2+4....you get the picture...

I'm wondering what would be the best set-up for these 4 panels.
Searios is offline   Reply With Quote
Old 07-17-2016, 06:22 AM   #9
Senior Member
 
City: Hong Kong
Country: Hong Kong
Join Date: Nov 2012
Posts: 210
This is my Bimini...:
Attached Images
 
Searios is offline   Reply With Quote
Old 07-17-2016, 08:23 AM   #10
Guru
 
foggysail's Avatar
 
City: Ashland, MA
Country: United States
Vessel Model: 1990 Silverton 40 aftcabin
Join Date: Jul 2016
Posts: 569
I have both 12v and 24v systems on my boat, only the 12v is connected to the solar. But why are those of you who have higher voltage panels going with higher voltages? The only advantage I can see is being able to use smaller wire from the panels to your MPPT controller/regulator. Personally and I do mean for me, I don't want any subsystems that operate above 48v for safety reasons.

My panels operate in parallel mode with two each wired together using #10 wire. So I have a total of 4 wires from my panels to a solar regulator......have to look at to get the manufacturer's name but it is a quality regulator not a $10 Ebay special. By the way, those inexpensive things on Ebay do work although I doubt they provide battery equalization.
foggysail is offline   Reply With Quote
Old 07-17-2016, 08:11 PM   #11
Senior Member
 
City: Hong Kong
Country: Hong Kong
Join Date: Nov 2012
Posts: 210
Its not for safety:https://www.physics.ohio-state.edu/~...l_current.html
Searios is offline   Reply With Quote
Old 07-17-2016, 09:58 PM   #12
Guru
 
healhustler's Avatar
 
City: Longboat Key, FL
Country: USA
Vessel Name: Bucky
Vessel Model: Krogen Manatee 36 North Sea
Join Date: Oct 2009
Posts: 4,130
Great info, DD. I've gone to quite a bit of trouble to clear my pilothouse roof and remove the likelihood of shading. Sounds like it may have been worth it.
__________________
Larry

"I'd rather be happy than dignified".
healhustler is offline   Reply With Quote
Old 07-17-2016, 10:58 PM   #13
Guru
 
AusCan's Avatar
 
City: Adelaide
Country: Australia
Vessel Name: Kokanee
Vessel Model: Cuddles 30 Pilot House Motor Sailer
Join Date: Jul 2012
Posts: 1,959
Good info.

I'm in the process of working out the best layout for panels. I was concerned about the shade from my vhf antenna, but it looks like a narrow shadow like that has only minor effect. Makes my roof layout plans a little simpler.
AusCan is offline   Reply With Quote
Old 07-17-2016, 11:07 PM   #14
Guru
 
BruceK's Avatar
 
Join Date: Oct 2011
Posts: 7,387
Thanks DD. Very helpful.
__________________
BruceK
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Old 07-18-2016, 08:02 AM   #15
Guru
 
foggysail's Avatar
 
City: Ashland, MA
Country: United States
Vessel Model: 1990 Silverton 40 aftcabin
Join Date: Jul 2016
Posts: 569
Quote:
Originally Posted by Searios View Post


????
foggysail is offline   Reply With Quote
Old 07-18-2016, 10:29 PM   #16
Senior Member
 
Diesel Duck's Avatar
 
City: discomfort.reactants.peanuts
Country: Colombia, South America and Huatulco, Mexico
Join Date: Sep 2014
Posts: 452
Quote:
Originally Posted by Searios View Post
This is my Bimini...:

Do I see dedicated racks built within the Bimini structure to support 12 solar panels? If so, I like it!
__________________
Diesel Duck
*For Sale or Trade this oceanfront Mexican villa (www.QuintaAlegria.com) for the right 'Trawler' - Nordhavn, Kadey Krogen, Diesel Duck or ???
Diesel Duck is offline   Reply With Quote
Old 07-18-2016, 11:12 PM   #17
Guru
 
dhays's Avatar
 
City: Gig Harbor
Country: United States
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
Posts: 5,034
I finally had a chance to view the vid. I am amazed at how devastating any shade is to the output. It means that in my case a pilothouse roof installation would very limited if the sun drops low enough for the arch to cast a shadow on the panels. It makes it appear that in my case I would either have to mount them at the arch level, or just not bother.
__________________
Regards,

Dave
SPOT page
dhays is offline   Reply With Quote
Old 07-25-2016, 09:18 PM   #18
Senior Member
 
City: Hong Kong
Country: Hong Kong
Join Date: Nov 2012
Posts: 210
Quote:
Originally Posted by Diesel Duck View Post
Do I see dedicated racks built within the Bimini structure to support 12 solar panels? If so, I like it!
Yes, the middle section frame holds 4 panels. I have also decided to install them in parallel only due to the video, so thanks for posting it..
Searios is offline   Reply With Quote
Old 07-26-2016, 11:15 AM   #19
Senior Member
 
City: Houston
Country: USA
Join Date: Jun 2015
Posts: 229
I have read that when a solar panel is shaded, it will automatically reduce its output by 50% to "protect itself." I don't pretend to understand this, but it is consistent with the results in the video. The video also indicates that if more than one panel is shaded, output may be almost eliminated.

I have also read that "microinverters" (e.g., Enphase) can be installed on panels to solve this problem. I don't know anything about this, either, but maybe others do.
Cottontop is offline   Reply With Quote
Old 07-26-2016, 12:20 PM   #20
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,549
Quote:
Originally Posted by Cottontop View Post
I have read that when a solar panel is shaded, it will automatically reduce its output by 50% to "protect itself." I don't pretend to understand this, but it is consistent with the results in the video. The video also indicates that if more than one panel is shaded, output may be almost eliminated.

I have also read that "microinverters" (e.g., Enphase) can be installed on panels to solve this problem. I don't know anything about this, either, but maybe others do.
I would read up more on shading...I don't believe that power is reduced to protect themselves (solar panels) and there are variations in panels themselves aND how they are set up.

Here is a link I found helpful...along with many other generic internet articles...

mv.VikingStar: Solar Panels on the Boat - Modeling and Performance
__________________

psneeld is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 06:37 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012