Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-17-2010, 02:11 PM   #85
Maniacal Engineer
 
barts's Avatar
 
1971 25' Tradewind
Menlo Park , California
Join Date: Jan 2010
Posts: 1,224
Images: 1
Blog Entries: 4
Quote:
Originally Posted by Phoenix View Post
Costco now has a 4x15 watt solar panel kit that is rated at 60 watts total. From practical experience, is that enough output to be useful for boondocking, or are two kits needed? Our 19-foot Bambi doesn't have much open space on the roof, so I am looking at putting these on our tonneau cover. However, I am concerned about them being so accessible, especially where they are down low and visible. Also, I'm not sure they will be as efficient, since they may be in shadow longer during the day if mounted on the tonneau.

Opinions welcomed...
We bought two sets about a month ago, but returned them. For temporary usage, they seem adequate but for permanent installation they appear lacking in UV resistance. In particular, the case for each panel is plastic of some sort, and the cabling looks like outdoor lamp cord.

If you're careful about using juice, 60W of solar panel will definitely help extend your boondocking time.

Note that these panels are rated for RV use, and the price is reasonable.

- Bart
__________________

__________________
Bart Smaalders
Menlo Park, CA
http://tinpickle.blogspot.com
http://smaalders.net/barts
barts is offline   Reply With Quote
Old 05-17-2010, 04:07 PM   #86
Rivet Master
 
Wabbiteer's Avatar
 
1973 27' Overlander
1972 29' Ambassador
St. Paul , Minnesota
Join Date: Apr 2006
Posts: 1,955
Images: 2
Blog Entries: 2
The 15w thin-film panels available everywhere are junk. Just say no.

The AMSolar panel "is designed to be a perfect match to the new (sic) Current Boosting MPPT Solar Charge Controllers" is good and bad, but for $3 a watt is a tempting deal. Be warned that wiring direct or using a pulse-width-modulated (PWM) without a multi-power-point-tracking (MPPT) charge controller you'll loose 30% of the wattage via power mismatch by clamping the 21V panels down to a 12V battery.

A decent MPPT charger will set you back $125 and up.

The smaller the panel (power/size) the higher the price premium. Sun Electric panels are as low as $1.80 a watt but they sell out of smaller panels rapidly.

I have two 50w Sun panels waiting to install
__________________

__________________

Wabbiteer is offline   Reply With Quote
Old 05-17-2010, 05:42 PM   #87
Rivet Master
Commercial Member
 
lewster's Avatar
 
Vintage Kin Owner
Naples, FL , Hood River, OR
Join Date: Dec 2005
Posts: 7,306
Be careful out there!

All solar IS NOT created equal and a watt is not a watt when some panels have a higher open circuit voltage (OCV). It takes a sophisticated MPPT (multi point power tracking) charge controller to really get the benefit of higher OCVs.

The controllers that AM Solar use take this higher voltage and boost the charge amperage. I have seen over 30 amps to the batteries on my service van with 4 X 100 watt AM-100 panels and their HPV-30DR 3-stage charge controller. It has been keeping the house and starting batteries in my van perfectly charged for 3 years now.

Cheap equipment is just that.....C-H-E-A-P. Maybe to maintain a battery system while in storage (I would use the 15 watt system from BatteryMinder for that), but for a boondocking oriented charging system...... NOT!

If you're going to spend the bucks, do it right or don't do it at all!

Just my professional opinion....of course.
__________________
Lew Farber...ABYC Certified Master Marine Electrician...RVIA Certified Master Tech ...AM Solar Authorized Installation Center...AIRSTREAM Solar & Electrical Specialist...Micro Air 'Easy Start' Sales and Installations
lewster is offline   Reply With Quote
Old 05-17-2010, 07:36 PM   #88
2 Rivet Member
 
2010 27' FB International
Portland , Oregon
Join Date: May 2010
Posts: 24
On the discussion of AGM versus other battery types - I believe one of the best reasons to use AGM batteries with solar is their higher charging efficiency. Flooded and Gel batteries have charging efficiency in the range of 85% - that means that 15% of the capacity of your solar panels is thrown away by the battery. AGM batteries can have close to 95% charging efficiency.

So, using AGMs instead of other battery types is like adding 10-12% more panels to your roof.

AGMs have other benefits as well - but this one seems the most compelling for solar - where you're trying to capture every spare scrap of energy.
tfmkevin is offline   Reply With Quote
Old 05-17-2010, 07:39 PM   #89
Rivet Master
Commercial Member
 
lewster's Avatar
 
Vintage Kin Owner
Naples, FL , Hood River, OR
Join Date: Dec 2005
Posts: 7,306
Quote:
Originally Posted by tfmkevin View Post
On the discussion of AGM versus other battery types - I believe one of the best reasons to use AGM batteries with solar is their higher charging efficiency. Flooded and Gel batteries have charging efficiency in the range of 85% - that means that 15% of the capacity of your solar panels is thrown away by the battery. AGM batteries can have close to 95% charging efficiency.

So, using AGMs instead of other battery types is like adding 10-12% more panels to your roof.

AGMs have other benefits as well - but this one seems the most compelling for solar - where you're trying to capture every spare scrap of energy.
Right you are!

Lifelines are the ONLY batteries that we use when we do solar charging system installations. Their super low internal resistance is the primary reason, along with their long life. Using liquid lead/acid batteries sort of defeats the purpose.
__________________
Lew Farber...ABYC Certified Master Marine Electrician...RVIA Certified Master Tech ...AM Solar Authorized Installation Center...AIRSTREAM Solar & Electrical Specialist...Micro Air 'Easy Start' Sales and Installations
lewster is offline   Reply With Quote
Old 05-18-2010, 07:03 AM   #90
More than one rivet loose
 
thecatsandi's Avatar

 
Currently Looking...
Keymar , Maryland
Join Date: Feb 2006
Posts: 3,754
I would also check with Sunelco 1-888-SUNELCO (786-3526) here in Montana. They helped me add panels to my trailer and will be installing a 1Kw array on my roof next week. They are not the cheapest but they will bet you the best set up for your situation.
__________________
Michelle TAC MT-0
Sarah, Snowball

Looking for a 1962 Flying Cloud

thecatsandi is offline   Reply With Quote
Old 05-28-2010, 07:59 AM   #91
Rivet Master
 
arodriguez60's Avatar
 
1959 22' Flying Cloud
1969 25' Tradewind
1983 34' Limited
fairview , New Mexico
Join Date: Mar 2005
Posts: 574
Images: 85
I'm going to try the Rogue controller it is a mttp controller made in Oregon. It is a 30 amp ,capable of 12 or 24 volt input with a 12 volt output. so I can use my panels in series in order to minumize my power loss from low voltage high amperage losses. I'll be using 24 volts with a lower amp with the same wattage. This will make for a more effiecient use of the limited acreage on the roof of my AS.
Attached Images
 
__________________



Avion C11
1959 Flying Cloud
1969 Tradewind
1973 Safari
1983 34 ft Limited
2004 F250 superduty ext cab
2014 F350 longbed superduty crewcab
arodriguez60 is offline   Reply With Quote
Old 05-28-2010, 09:50 AM   #92
4 Rivet Member
 
eheffa's Avatar
 
2008 25' Safari FB SE
Victoria , BC
Join Date: Jun 2008
Posts: 333
Quote:
Originally Posted by arodriguez60 View Post
I'm going to try the Rogue controller it is a mttp controller made in Oregon. It is a 30 amp ,capable of 12 or 24 volt input with a 12 volt output. so I can use my panels in series in order to minumize my power loss from low voltage high amperage losses. I'll be using 24 volts with a lower amp with the same wattage. This will make for a more effiecient use of the limited acreage on the roof of my AS.

I'm not sure that will work Anthony. The AM Solar panels I have put out 24V under no load & cloudy skies, so series installation would potentially get you up to 48V. I would suggest that you check the panel output of the panels you are going to install...

Maybe I'm repeating myself unnecessarily but if your roof space is quite limited, you can actually install the panels over some of the plumbing vents as a way to gain more mounting room.

-evan
eheffa is offline   Reply With Quote
Old 05-28-2010, 12:28 PM   #93
Rivet Master
 
Wabbiteer's Avatar
 
1973 27' Overlander
1972 29' Ambassador
St. Paul , Minnesota
Join Date: Apr 2006
Posts: 1,955
Images: 2
Blog Entries: 2
http://www.roguepowertech.com/documents/MPT3024B1.pdf

"The MPT-3024 will operate with an input voltage from the PV array of up to 60 volts... ....The absolute maximum input voltage for the MPT-3024 is 75 volts."

Winter happens. (I know, I'm in Minnesota)

Total Volts-Open-Circuit plus the degree Celsius multiplier of the worst case winter weather.

RV-100 VOC 24.8 - AM does not list the temp coefficient so insert BP's (11110)mV/C" so for every 10 degrees Celsius colder the voltage can possibly jump 1.21 Volts.

The tricky part is at what temperature AM Solar rates their voltages at, NOCT (Nominal Operating Cell Temperature) at 25C or a more realistic 47C like the example BP panel does. If the rating is at 47C and you see 5F or -15C that is 7.5V extra on each panel for 32.3V per panel ~ now add in cloud-edge effect where the water droplets can magnify sunlight up to 125% of normal and you've just put 80V on the controller with 75V maximum.

Remember that "Cloud-Edge" 125% after the temp coefficient adjustment when doing your calculations - the internet is littered with people who had a cold snap fry their charge controllers....

Personally I went with the Outback MX60 (150VDC abs limit) picked up on ebay used for not much more than the Rouge lists for new...
__________________

Wabbiteer is offline   Reply With Quote
Old 05-28-2010, 12:53 PM   #94
Rivet Master
 
arodriguez60's Avatar
 
1959 22' Flying Cloud
1969 25' Tradewind
1983 34' Limited
fairview , New Mexico
Join Date: Mar 2005
Posts: 574
Images: 85
I live in the southwest so I don't fore see it getting that cold .I understand that the panels will produce more in the colder temps. I may try the panels in parrallel first and see how well they perform.
__________________



Avion C11
1959 Flying Cloud
1969 Tradewind
1973 Safari
1983 34 ft Limited
2004 F250 superduty ext cab
2014 F350 longbed superduty crewcab
arodriguez60 is offline   Reply With Quote
Old 05-31-2010, 08:46 AM   #95
Tool Hoarder
 
Currently Looking...
West , California
Join Date: May 2010
Posts: 907
Images: 3
Hi Eheffa I am new to Airstreaming and am considering solar for my 1965 Sovereign. I am going to gut and re wire my rig. I want to avoid putting a hole in the roof if I can. Any thoughts on battery placement, and where to run the wires to the roof? Thank you so much for your contribution! You actually set you solar panels up the exact way I want mine.
marzboy is offline   Reply With Quote
Old 05-31-2010, 11:01 AM   #96
4 Rivet Member
 
eheffa's Avatar
 
2008 25' Safari FB SE
Victoria , BC
Join Date: Jun 2008
Posts: 333
Quote:
Originally Posted by marzboy View Post
Hi Eheffa I am new to Airstreaming and am considering solar for my 1965 Sovereign. I am going to gut and re wire my rig. I want to avoid putting a hole in the roof if I can. Any thoughts on battery placement, and where to run the wires to the roof? Thank you so much for your contribution! You actually set you solar panels up the exact way I want mine.
Hi marzboy,

I am no expert on these issues but I shared your anxiety around drilling through the roof & spent quite a while trying various plans to avoid this. After dealing with a few leaks including one discovered during my Panel Installation, I now see that I can do a better job of penetrating the roof & sealing the hole than the factory does.

By placing the Distribution box under a Solar Panel & having it fully sealed on a base of Dicor, it is really not really a high risk for leaks later; esp. when you compare it to the other through-hull fittings that have full exposure to the UV & the wet. So, I would suggest if you can't make use of the reefer vent, that you plan to run your wire through at some point where you can have one of the panels over top as an extra level of protection. It's not really a big deal once you get over the angst of drilling through that virginal aluminum.

The reefer vent is an attractive conduit to the lower / interior trailer, but in my case it meant more trouble fishing wire forward to the battery bank. (The factory supplied 10 AWG pre-wire was too small unfortunately.) In the end, the easiest thing with the shortest length run was to go through the roof.

As an added benefit of having the solar panels over the bathroom & shower vents, I can now leave these vents open all the time in storage without snow & rain getting in. They still work just fine.

If you are stripping the interior, your options for running wires etc should be wide open. I don't think one hole through the roof with the D-Box & panel over it should be much of an issue at all.

As far as battery placement goes, Lewster would probably be a much better resource for that sort of question. If you go with AGM batteries, you have many more options as they can be in your living space but there would be many variables such as power requirements etc that enter into what & how many batteries you will want. I would defer to Lewster or others on questions around that though.

I hope that helps. Enjoy your project.

-evan
eheffa is offline   Reply With Quote
Old 11-27-2010, 10:07 AM   #97
Capt W
 
2013 31' Classic
Jefferson , Massachusetts
Join Date: Nov 2010
Posts: 78
Images: 1
Blog Entries: 1
Thanks for the great post

Excellent step by step description. My wife and I just bought our first AS (25' Safari SS). We take delivery in couple weeks. The 38' Shannon Ketch we have been sailing for several years was totaled in a fire at a marina. So we are taking advantage of this calamity to fulfill another dream, to see as many national parks as we can between Massachusetts and Alaska. We plan to set off this spring.

The boat had an 80 watt solar panel that worked very well and I would like to install panels on the AS, your posting and link will be a big help when I get into the project.

Thanks again.

W
wrochdvm is offline   Reply With Quote
Old 12-01-2010, 12:31 PM   #98
4 Rivet Member
 
eheffa's Avatar
 
2008 25' Safari FB SE
Victoria , BC
Join Date: Jun 2008
Posts: 333
Quote:
Originally Posted by wrochdvm View Post
Excellent step by step description. My wife and I just bought our first AS (25' Safari SS). We take delivery in couple weeks. The 38' Shannon Ketch we have been sailing for several years was totaled in a fire at a marina. So we are taking advantage of this calamity to fulfill another dream, to see as many national parks as we can between Massachusetts and Alaska. We plan to set off this spring.

The boat had an 80 watt solar panel that worked very well and I would like to install panels on the AS, your posting and link will be a big help when I get into the project.

Thanks again.

W
Thanks for the feedback W.

Good luck on your new Airstream & may you have many enjoyable days out in the back country...

-evan
__________________

eheffa is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar Panel Installation 69Overlander Generators & Solar Power 28 03-03-2013 08:18 PM
AM Solar installation on a Safari hshovic Generators & Solar Power 12 04-09-2011 10:27 PM
Solar panel installation jglase Generators & Solar Power 9 11-30-2006 09:47 PM
Help on solar panel installation Les Gilliam Generators & Solar Power 3 11-27-2002 08:28 PM
Solar Installation cactushead 2001 Safari 19 10-21-2002 05:56 PM


Featured Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 04:01 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.