Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 21-01-2017, 12:15   #46
Registered User

Join Date: Oct 2014
Location: Panama City Beach, FL
Boat: Beneteau 343
Posts: 145
Re: Opinions on solar power

You have about the same energy budget as my boat. A while ago I upgraded house batts to 4 6v golf cart batts = 450 AH. I realize 200 watts isn't going to get it done perfectly but right now I charge the batts via engine as I go from point A to point b, never staying away from shore power for more than a week so I frequently get fully charged in a slip. As I slow down and spend more time in one place not in a slip I was thinking two 100 watt flex panels might give me a good entry into solar and cut meaningful engine run times but not all. And I use a Yeti with dry ice which lasts quite some time so Fridg dependence goes down. My week long adventures are not full cruising so I was going to plan for 4 flex panels on Bimini and start with 2 as I further understand my usage trends.
__________________

__________________
EmeraldCoastSailor is offline   Reply With Quote
Old 21-01-2017, 15:03   #47
Registered User
 
buzzstar's Avatar

Join Date: Apr 2012
Posts: 1,212
Re: Opinions on solar power

You have received lots of good advice, with corrections and explanations too. If you are not going to use refrigeration right away, I suggest start with your 240 using hard panels, but layout and set up for at least one more panel, perhaps two, so you can increase capacity if and when needed. You may also want to consider such things as wind or even, as mentioned, a small generator. AND do not forget the batteries, their storage capacity is vital. While I am sure you know, and the previous posters do too, although I did not see it in my quick scan of the thread, rarely, if ever, do alternate energy sources live up to their advertised output specs.
__________________

__________________
Brian, sometimes called "Old California"
Still learning after all these years
buzzstar is online now   Reply With Quote
Old 21-01-2017, 18:32   #48
Registered User

Join Date: Feb 2015
Location: En route to Bahamas
Boat: Caliber 47
Posts: 89
Re: Opinions on solar power

Quote:
Originally Posted by ErikFinn View Post
and I thought I made a special effort to make it exceptionally clear..


I understood you!
__________________
Caliber40 is offline   Reply With Quote
Old 21-01-2017, 18:35   #49
Registered User
 
ErikFinn's Avatar

Join Date: Feb 2011
Location: Malaysia, Thailand
Boat: Beneteau Oceanis 430
Posts: 806
Re: Opinions on solar power

Quote:
Originally Posted by Caliber40 View Post
I understood you!
Thank You!
__________________
ErikFinn is offline   Reply With Quote
Old 21-01-2017, 19:23   #50
Registered User
 
buzzstar's Avatar

Join Date: Apr 2012
Posts: 1,212
Re: Opinions on solar power

Quote:
Originally Posted by ErikFinn View Post
and I thought I made a special effort to make it exceptionally clear..
You clearly did. In fact so you did it so well that it deserved repetition. But not so well that it did not need repetition in different words.
__________________
Brian, sometimes called "Old California"
Still learning after all these years
buzzstar is online now   Reply With Quote
Old 21-01-2017, 20:28   #51
Registered User
 
Kinta Ray's Avatar

Join Date: Jun 2013
Location: Live Aboard-Australia
Boat: 38' Crowther Windspeed
Posts: 31
Re: Opinions on solar power

Regarding the lifespan of the flexible panels, I have been told that a regular clean and application of polish will extend the life to close that of a hard panel. If they become clouded they can be restored with a mild cut and polish, just don't get too carried away or leave them unpolished as this speeds up the clouding. Hope this helps.
__________________
Kinta Ray is offline   Reply With Quote
Old 21-01-2017, 22:28   #52
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2005
Boat: Outbound 44
Posts: 4,343
Re: Opinions on solar power

Quote:
Originally Posted by Kinta Ray View Post
Regarding the lifespan of the flexible panels, I have been told that a regular clean and application of polish will extend the life to close that of a hard panel. If they become clouded they can be restored with a mild cut and polish, just don't get too carried away or leave them unpolished as this speeds up the clouding. Hope this helps.
Besides being yet another maintenance item, it sounds more like marketing hype than reality, at least in the tropics. Also flex panels have a shorter life because they flex. Lots of good reasons to use flex panels, but longevity as compared to ridgid panels isn't one of them.
__________________
Paul L is offline   Reply With Quote
Old 21-01-2017, 22:30   #53
Registered User

Join Date: Aug 2015
Location: Marina del Rey
Boat: Hunter 31
Posts: 343
Re: Opinions on solar power

This is a recurrent topic and the typical suggestion is add more batteries and solar. I disagree. The battery capacity is not that important as long as it can last you through the night with some reserve. So, how do you generate electricity on board:

1) Run the engine. On a typical 30-35 boat, you will generate 80 A/H and use 1/5 gph in fast idle. By far the cheapest and simplest method. You may need to upgrade the alternator but that is inexpensive.

2) Next, you can install solar. Every 100 watts of panel will give you 25 AHr per day or the equivalent of 20 min engine run-time. You have to avoid shading, use mppt controllers and maximize the angle to the sun. I believe some solar is essential as a backup (radio, charging starting battery if dead, etc.) But the majority of you AHrs will come from the engine.

3) If you find you are running the engine a lot (more than 300 hours a year), you may consider a generator.

Lastly, do heed the advice to look at the whole system. For example, running the engine is efficient only in bulk charging mode, which means an appropriate battery capacity and state-of-charge and so on.

Happy reading

S/V Pizzazz
__________________
Pizzazz is offline   Reply With Quote
Old 21-01-2017, 23:18   #54
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,439
Re: Opinions on solar power

Quote:
Originally Posted by Pizzazz View Post
This is a recurrent topic and the typical suggestion is add more batteries and solar. I disagree. The battery capacity is not that important as long as it can last you through the night with some reserve. So, how do you generate electricity on board:

1) Run the engine. On a typical 30-35 boat, you will generate 80 A/H and use 1/5 gph in fast idle. By far the cheapest and simplest method. You may need to upgrade the alternator but that is inexpensive.

2) Next, you can install solar. Every 100 watts of panel will give you 25 AHr per day or the equivalent of 20 min engine run-time. You have to avoid shading, use mppt controllers and maximize the angle to the sun. I believe some solar is essential as a backup (radio, charging starting battery if dead, etc.) But the majority of you AHrs will come from the engine.

3) If you find you are running the engine a lot (more than 300 hours a year), you may consider a generator.

Lastly, do heed the advice to look at the whole system. For example, running the engine is efficient only in bulk charging mode, which means an appropriate battery capacity and state-of-charge and so on.

Happy reading

S/V Pizzazz
Be wary of heeding the advice of people who think that A/H is a measure of alternator output.

Alternators/generators are great for the initial bulk charging of a LA battery when it is at a low state of charge, it is a very wasteful way of trying to put the last 10-15% of charge back into the battery because it will take hours of engine time. This is where solar comes into its own.
__________________
StuM is offline   Reply With Quote
Old 22-01-2017, 04:04   #55
Registered User

Join Date: Aug 2015
Location: Marina del Rey
Boat: Hunter 31
Posts: 343
Re: Opinions on solar power

Quote:
Originally Posted by StuM View Post
Be wary of heeding the advice of people who think that A/H is a measure of alternator output.
Alternators/generators are great for the initial bulk charging of a LA battery when it is at a low state of charge, it is a very wasteful way of trying to put the last 10-15% of charge back into the battery because it will take hours of engine time. This is where solar comes into its own.
Stu,
80 A/H means 80 amps per hour which when coupled with the 0.2 gph, gives the OP enough information to figure out you can produce 5x80=400AHr per gallon. So, it is quite alright if non-standard.

I do not really see your motivation for commenting on every CF post, nitpicking, without adding new ideas.
__________________
Pizzazz is offline   Reply With Quote
Old 22-01-2017, 04:41   #56
Registered User

Join Date: May 2014
Location: USA
Boat: 41' yawl
Posts: 597
Re: Opinions on solar power

Quote:
Originally Posted by Pizzazz View Post
Stu,
80 A/H means 80 amps per hour which when coupled with the 0.2 gph, gives the OP enough information to figure out you can produce 80A*5hr=400AHr per gallon. So, it is quite alright if non-standard.

I do not really see your motivation for commenting on every CF post, nitpicking, without adding new ideas.

Please read posts 26 and 27. It's not that your units are non-standard, it's that they are incorrect! You are being helpful, and Stu is trying to help you be even more helpful.

I see that you mean to say is Amp hour per hour. That's easier expressed as just Amp (see correction above).

Or , if you prefer, the amp hour donkey giraffe per hour donkey giraffe.
__________________
chris95040 is offline   Reply With Quote
Old 22-01-2017, 05:32   #57
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,439
Re: Opinions on solar power

Quote:
Originally Posted by Pizzazz View Post
Stu,
80 A/H means 80 amps per hour which when coupled with the 0.2 gph, gives the OP enough information to figure out you can produce 5x80=400AHr per gallon. So, it is quite alright if non-standard.

I do not really see your motivation for commenting on every CF post, nitpicking, without adding new ideas.
No such thing as Amps per hour.
__________________
StuM is offline   Reply With Quote
Old 22-01-2017, 05:36   #58
Registered User

Join Date: Nov 2007
Location: Probably and anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 3,336
Re: Opinions on solar power

Quote:
Originally Posted by Pizzazz View Post
1) Run the engine. On a typical 30-35 boat, you will generate 80 A/H and use 1/5 gph in fast idle. By far the cheapest and simplest method. You may need to upgrade the alternator but that is inexpensive.
Unless you want to get the batteries fully charged which would mean running the engines for hours, no matter what size of alternator you fit. That last 20% or so will still take something like 4 hours.
__________________
conachair is offline   Reply With Quote
Old 22-01-2017, 06:37   #59
Registered User

Join Date: Dec 2016
Location: Brazil
Boat: Custom Swedish Vindö 50 (35 ft)
Posts: 178
Re: Opinions on solar power

I would suggest first trying to reduce your consumption on board by using only LED lights and cutting power use where possible. Since you don't mention anything about your fridge, it's hard to know what its power draw is. 240w of solar might be enough to keep up with your power needs, but all the laptop, Ipad, phone etc. charging may be too much to keep up with. FWIW, I have only 90w of solar at present and a 210a battery bank and will soon install a monster 270w (60 cell/30v) panel over my bimini to bring my total solar up to 360w. I'm pretty sure it will be overkill for my power needs. I have an Engel fridge (very low power consumption), all LED lighting, no electric pumps (except bilge) and a normal amount of electronics. I figure I use less than 50ah a day at anchor. I'm hoping my solar array will generate about twice my energy needs on most days. It's always cheaper in the long run to reduce energy consumption than it is to generate more energy (especially if you have to buy a generator!).
__________________
Copacabana is online now   Reply With Quote
Old 22-01-2017, 06:50   #60
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,439
Re: Opinions on solar power

Quote:
Originally Posted by conachair View Post
Unless you want to get the batteries fully charged which would mean running the engines for hours, no matter what size of alternator you fit. That last 20% or so will still take something like 4 hours.
Apparently pointing out bad advice like that is just nitpicking without adding new ideas.
__________________

__________________
StuM is offline   Reply With Quote
Reply

Tags
solar

Thread Tools
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
Opinions about Aurinco solar panels flandria Electrical: Batteries, Generators & Solar 11 24-04-2017 17:31
Wondering why more power boats aren't using solar power to recharge house batteries? JohnEasley Powered Boats 36 05-07-2016 20:20
Solar power - length of solar day - does this make sense roland stockham Electrical: Batteries, Generators & Solar 16 12-01-2016 05:03
Info on Garmin 498 C Sounder. Opinions? Transome mounted Transducer? Opinions? chuck711 Marine Electronics 0 14-01-2007 16:06


Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 11:55.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.