Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 23-11-2022, 17:40   #1
Registered User

Join Date: Apr 2007
Location: New England/FL
Boat: vineyard vixen 28
Posts: 962
Which to use: One panel or 2 when shaded

I put up a post about whether to hook up 2 sets of panels in series or parallel, but this one is about if shaded whether or not I should put on a single 100W panel that goes across the top of the dodger or put 2 50W , one on each side of the dodger.

See pic, the boom will be over the top of the dodger, so I am assuming part will be shaded. The boat on the mooring will face south, so the boom will cast a shadow on each side of the dodger throughout the day. Sailing is a different story of course.

My question is, if I have a single 100, or I could even go to 175W panel , that I put across the dodger, or put 2 50s (best I can fit with 2) , one on each side. I am not sure when the boom casts its shadow how effective a single 100W/175W panel becomes. I will certainly get most of 50W from the unshaded panel plus something from the shaded panel.

The bimini will take a single 175 across the back of it. That seems the best I can do, there are holes in back section for the backstays, and windows in the front section to look up to see the mainsail.
Attached Thumbnails
Click image for larger version

Name:	solarpanels.jpg
Views:	27
Size:	373.9 KB
ID:	267857  
jbinbi is offline   Reply With Quote
Old 23-11-2022, 18:42   #2
Registered User

Join Date: Jun 2013
Location: canada
Posts: 4,231
Re: Which to use: One panel or 2 when shaded

the 50w in total sun may put out more then a 100 or 175 with the boom across it. but hard to know for sure unless you test both... generally a small shaded part will take out most of the power. its' definatlly not 1:1 of shaded area to power loss

if you get 2 50's you'd also need 2 controllers. having one shaded and one unshaded panel on same controller you just end up back where you started of losing a lot with the shade.
smac999 is offline   Reply With Quote
Old 23-11-2022, 19:13   #3
Registered User

Join Date: May 2021
Boat: Passport 41
Posts: 199
Re: Which to use: One panel or 2 when shaded

On a mooring, If you leave the boom above the dodger, even with two panels it is likely to cast a shadow on one or the other during parts of the day. If you ease the main sheet and lock the boom to either side with a preventer you don't have to worry about that
LifesBetterWhenYoureBeating is online now   Reply With Quote
Old 23-11-2022, 19:34   #4
Marine Service Provider
 
boatpoker's Avatar

Join Date: Nov 2008
Location: Port Credit, Ontario or Bahamas
Boat: Benford 38 Fantail Cruiser
Posts: 6,046
Re: Which to use: One panel or 2 when shaded

I have two 315 Watt panels on my pilothouse (avatar) each independent with their own controller. My mast and riding sail (which is up all the time) are the shadow issue. It is not uncommon to see one panel put out 2 or 3 amps while the other puts out 30 amps or more.

If it was one panel I might get a total of 4 or 5 amps instead of a total of 33amps.
__________________
If you're not laughing, you're not doin' it right.
boatpoker is online now   Reply With Quote
Old 23-11-2022, 21:36   #5
Registered User
 
Uncle Bob's Avatar

Join Date: May 2010
Location: Sydney Australia
Boat: Fisher pilothouse sloop 32'
Posts: 3,152
Re: Which to use: One panel or 2 when shaded

^^^^^^^^^^
This, multiple panels is a no brainer. Do it and move on.
__________________
Rob aka Uncle Bob Sydney Australia.

Life is 10% the cards you are dealt, 90% how you play em
Uncle Bob is offline   Reply With Quote
Old 24-11-2022, 01:02   #6
Registered User
 
Rustic Charm's Avatar

Join Date: Jun 2011
Location: Tasmania, Australia
Boat: Bieroc 36 foot Ketch
Posts: 4,934
Re: Which to use: One panel or 2 when shaded

I’m new to this stuff as well. I’m intending on putting two 200w panels on my pilot house roof. Which is under the boom. My intention was to have a controller for each…. ?
Rustic Charm is offline   Reply With Quote
Old 24-11-2022, 06:45   #7
Marine Service Provider
 
boatpoker's Avatar

Join Date: Nov 2008
Location: Port Credit, Ontario or Bahamas
Boat: Benford 38 Fantail Cruiser
Posts: 6,046
Re: Which to use: One panel or 2 when shaded

Quote:
Originally Posted by Rustic Charm View Post
Iím new to this stuff as well. Iím intending on putting two 200w panels on my pilot house roof. Which is under the boom. My intention was to have a controller for eachÖ. ?
Thats the way to do it.
__________________
If you're not laughing, you're not doin' it right.
boatpoker is online now   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Shaded Panels - Catamaran Boom ArranP Electrical: Batteries, Generators & Solar 53 14-01-2022 23:09
Are two partially shaded total 260W panels worth it Tenedos Electrical: Batteries, Generators & Solar 59 21-02-2019 08:52
New solar panel but which one? Cpt Balu Electrical: Batteries, Generators & Solar 18 09-09-2018 19:34
Outback 60 with Partially Shaded Panels zboss Electrical: Batteries, Generators & Solar 21 04-03-2015 19:20
Solar panels that will be partially shaded--which is better? autumnbreeze27 Electrical: Batteries, Generators & Solar 16 02-02-2014 15:21

Advertise Here


All times are GMT -7. The time now is 08:49.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.