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WestyDreamer Mon Jun 09, 2014 5:47 pm

I'd like to get a Solar Panel but have concerns about where I'd like to mount it or how large of a Panel I'd really need.

So here's my needs and question.

I currently have little DC needs.
I have a Truck Fridge and a 110ah Deep Cycle Battery and Battery Combiner.

My normal camping events usually only last about 2-4 days.
I have found that my deep cycle will normally carry the fridge for 2-3 days without starting or driving the Van to extend the batteries life.

So here's my thought about my needs of a Solar Panel.
I'd like to go with a smaller size Panel that I can make usable not hard mounted to the roof etc and just connect it when wanted sort of like one of those portable fold up units but without the cost.

Do you solar experts think that a smaller size say 30 or 50 watt solar panel will help extend my deep cycle. My thoughts are is that even if a small panel it would add continuous recharging thus extending the usable ah's of my deep cycle.

My original thoughts were to install a 100 watt Panel but they are like 4'x2' and due to size would have to be hard mounted whereas the smaller ones are about 2x2' and could be stored or packed as needed.

I'm thinking that due to there small size that I can store it easily and just set it on the roof or rig up a hanger to hang from the rain gutters etc when needed? :idea:

I truly have no need to hang a large solar panel on my roof that will be seldom used. I realize that many think that Biggers better but small solar panels are often used on small boats etc.

Anyone have a small one that works for there needs.
Your Thoughts :?:

realfstkid Mon Jun 09, 2014 6:19 pm

WestyDreamer wrote: I currently have little DC needs.
I have a Truck Fridge and a 110ah Deep Cycle Battery and Battery Combiner.


I have a very similar set up: TF-49 with a 106ah Deep Cycle Battery. Besides the fridge, I have the radio going pretty quietly part of the day, and I charge my cell phone in the evenings. I have a 120 watt solar panel, with an MPPT charger, and generally speaking, in the summer, with full sun--albeit not angled at the sun, mine is hard mounted to my racks--my charger enters sustain mode around noon, meaning that I have a good bit of extra capacity with the solar panel.

I would say that if you are looking to simply prolong your battery's life, you may get away with a 40-50 watt panel, but that being said, those fold up panels tend to be much smaller than 40-50 watt, and in my experience much more expensive. I paid $100 on CL for a brand new 120 watt PC 12v solar panel, and I know this isn't out of line with what others are paying for panels of this size, if you're willing to hunt out a deal.

The GoWesty one, at 80 watts, may just be able to run your system indefinitely if you have access to full sun, and you take the time to insure it's angled at the sun every so often:

GoWesty 80 Watt Compact Solar Panel

As for the idea of it being movable, I think this is key. I really wish mine was more movable, as you gain a LOT of power by being able to keep it angled directly at the sun, and it would be nice to have a 20' length of wire so I could park in the shade and then just run the panel out into the sunshine.

Hope that helps.

ThankYouJerry Mon Jun 09, 2014 7:53 pm

realfstkid wrote: WestyDreamer wrote: I currently have little DC needs.
I have a Truck Fridge and a 110ah Deep Cycle Battery and Battery Combiner.


I have a very similar set up: TF-49 with a 106ah Deep Cycle Battery. Besides the fridge, I have the radio going pretty quietly part of the day, and I charge my cell phone in the evenings. I have a 120 watt solar panel, with an MPPT charger, and generally speaking, in the summer, with full sun--albeit not angled at the sun, mine is hard mounted to my racks--my charger enters sustain mode around noon, meaning that I have a good bit of extra capacity with the solar panel.

I would say that if you are looking to simply prolong your battery's life, you may get away with a 40-50 watt panel, but that being said, those fold up panels tend to be much smaller than 40-50 watt, and in my experience much more expensive. I paid $100 on CL for a brand new 120 watt PC 12v solar panel, and I know this isn't out of line with what others are paying for panels of this size, if you're willing to hunt out a deal.

The GoWesty one, at 80 watts, may just be able to run your system indefinitely if you have access to full sun, and you take the time to insure it's angled at the sun every so often:

GoWesty 80 Watt Compact Solar Panel

As for the idea of it being movable, I think this is key. I really wish mine was more movable, as you gain a LOT of power by being able to keep it angled directly at the sun, and it would be nice to have a 20' length of wire so I could park in the shade and then just run the panel out into the sunshine.

Hope that helps.

Really good points re: 80W folding panel and 20' wire. I believe there may be 100-120W folding panels of similar size to the GW 80W folding panel available elsewhere. I would also recommend adding a second aux bat in tandem with the first.

madspaniard Mon Jun 09, 2014 8:00 pm

I got rid of my Yakima roof rack mounted 135w solar panel and now only carry a 120w foldable solar panel when needed. I have same aux battery and power needs as yours.

Edit: panel is 120w, not 100w

ThankYouJerry Mon Jun 09, 2014 8:05 pm

madspaniard wrote: I got rid of my Yakima roof rack mounted 135w solar panel and now only carry a 100w foldable solar panel when needed. I have same aux battery and power needs as yours.

Mad - Where did you get your 100W folding panel? Brand? Also, do you only run one aux bat?

PDXWesty Mon Jun 09, 2014 8:08 pm

http://www.thesamba.com/vw/forum/viewtopic.php?t=573136

The above thread has a good site listed for solar panels. Many of us bought their folding panels for less than $200. I got a 120 watt set up for $199. They seem to be out right now, but if you send them an email they will let you know when they are back in stock. I would highly recommend them. Pictures on page 2 of the thread.

madspaniard Mon Jun 09, 2014 8:10 pm

Sorry, I forgot, my panel is 120w. Only one 110 amps/hour aux battery for 12v fridge, Propex, radio and LED interior lights.

Info on the solar panel is here

http://www.thesamba.com/vw/forum/viewtopic.php?t=573136&highlight=solar

madspaniard Mon Jun 09, 2014 8:13 pm

From another thread, this is what I did to the 120w foldable panel posted in link above to make it better

madspaniard wrote:
I have this same foldable 120w panel. Three things I did to it. Converted all connections to MC4, got rid of the 16 awg wire extension for remote deployment of panel (made my own marine grade 12 awg extension and also upgraded all other small wire runs to 12 awg) and removed controller from panel (it only takes two very small bolts) so that I can use my on-board controller which used to control my rooftop solar panel. I still keep the controller I removed just in case I want to use this foldable panel in another vehicle.

PDXWesty Mon Jun 09, 2014 8:40 pm

This looks similar if you can't wait for one from Solarblvd.

http://www.goldrayenergy.com/product/120w-folding-solar-panel-kit/

Howesight Mon Jun 09, 2014 10:27 pm

I got the folding 100W panel from Renogy. When folded and in its case, it fits into the luggage rack on the pop top. I am impressed with the quality.

On Amazon, it sells for $270. For best results, I removed the charge controller and hard-mounted it into my Westy and had large-gauge wire cable made up as the cable it comes with (like almost all folding panels) is too small a gauge. It is best, by far, to mount the charge controller near the battery so that the temperature regulation of the charge controller can work appropriately and to reduce power loss. It is also very important to do the set up of your charge controller parameters (this takes some patience) to work with your specific battery(ies). My Trojan flooded lead-acid deep cycle battery must be charged at 14.8 volts. The charge controller factory pre-sets are at 14.2 volts (fine for Gel Cell, but not flooded), which slows down charging a lot if you don't take the time to do your set-up.

See here for the Amazon deal:

http://www.amazon.com/Renogy-Foldable-Suitcase-Battery-Charger/dp/B00HR8YNK6

There is only one other folding panel on the market 100W or more that actually fits in the Westfalia luggage rack and it's made here in Canada, hence the higher price. Here it is:

http://www.amazon.com/Go-Power-GP-PSK-120-Portable-Controller/dp/B009MIPH4K

I like GoWesty's Vanagon parts, but the price on their re-sold Zamp solar 80W kit is scandalous - - not worth the price when Renogy and others have the same or better quality. Here is GoWesty's folding solar panel. The charge controller is inferior to the one on the Renogy unit.

http://www.gowesty.com/ec_view_details.php?id=23897&category_id=338&category_parent_id=

WestyDreamer Tue Jun 10, 2014 1:09 pm

Maybe I should have been more clear about me Question.

My thoughts and Question was asking more about the smaller Wattage Panels.

My Hope was going with the Smaller size 50 Watt Solar Panel. They are only about 2'x2' square and thought that I could use it in multiple locations, luggage rack, poptop, etc ways once onsite and move it about into sunny areas etc by use of a interchangeable longer power cord.

But my question is would it add enough ah's back into my battery to supplement my needs. Which are manual.

If enough sunlight I don't see why not. Besides with this approach I have control over the panel Location / position..

Besides my friends who have the larger panels often don't have the portability of moving just there Panels to gather sunlight angle without re-positioning there campers once or twice and sometimes they don't have that opportunity so those huge panels are only performing like a much smaller panel anyway.. Also have seen many Panels hard mounted that once the Top is Popped the Panel was facing everything but the Sun. :oops:

Think I'll give the smaller Panel a try, going to mount the charge controller in the Van so heck I can always swap out the Panel if under performing. I'll let you know how it works out..
.

Syncro Jael Tue Jun 10, 2014 1:24 pm

I too wanted to add a small panel on top of the Westy.

Since I carry a kayak on my rack and have a Rocket Box on the other side I really needed to find a solution without taking my storage spot above the cab.

So I went this route and attached it to the top of the Thule Box. It is only 28W but during the day it can put a few AH into the house bank. It will also run my ARB Fridge/Freezer during the day.

http://www.selectsolar.co.uk/prod/404/powerfilm-r28-28w-rollable-solar-panel

I have a portable that I use when camping. But this way even when I am just parked hiking or biking, and do not want to set out the portable, I still have something going back into the batteries. Leaving your solar panel out on the ground might lead to someone borrowing it for a while? :shock:

It is pretty stealth up there on the Thule! 8)





Howesight Tue Jun 10, 2014 1:28 pm

Hey Westydreamer:

I think you ought to go for more than 50W. Remember that the greater power you have, the faster your re-charge will take place.

Those panels I referred to in my post above are all portable folding panels. Even the Renogy 100W panel that I strongly recommend uses the same footprint as the Renogy 50W panel since it is made up of two 50W panels.

It is really hard to protect a panel without some kind of "briefcase" cover. Just yesterday, I was transporting some heavy items in the back of my Westy, and I stupidly had the Renogy panel laying flat in the back, and, while I was turning a corner, a metal tool box tipped over right onto the panel. No damage resulted, but I won't chance that again. Without the "briefcase", the panel would have been ruined.

The beauty of all the panels I listed is that they will fit nicely in the luggage rack - - for storage, not for operation. You still have to take them down and put them in the sun and, if there is shade, park your van in the shade. Once I make my "luggage rack cover" (so many projects . . . ), I will leave the Renogy panel in the luggage rack all the time. As things are now, it is a theft risk to leave the panel there.

I thought about getting a smaller panel, but the storage problem is worse (how do you protect it?) and the cost savings, after getting your hardware, controller, wiring, etc, is minimal. You will want more watts later, guaranteed.

WestyDreamer Tue Jun 10, 2014 1:49 pm

Howesight wrote: I thought about getting a smaller panel, but the storage problem is worse (how do you protect it?) and the cost savings, after getting your hardware, controller, wiring, etc, is minimal. You will want more watts later, guaranteed.

I kind of agree with you about the larger Panels. But don't want to Hard mount one and don't want the price of hassle of storing or setup of the expensive 100 watt potable Panels. Also fear of losing the expensive store bought one when away from the camp site..

So my thoughts of transport or storage of the 50 watt panel would be..

I measured and thought about storing the 2x2' 50 watt panel on the underside of my Rear AC Unit. Kind of maybe making a slide to slide it into or maybe even a pair sling straps to fasten it to the underside of the AC Unit. Thus protecting it and utilizing un-used space.
It also measures less then 1 1/2" thick so it could also store or transport in in the upper bunk to protect it..

Hey who knows maybe it's a bad Brainfart but I'm stinking it just might server me needs.

crazyvwvanman Tue Jun 10, 2014 1:55 pm

A 50 watt panel aimed during the day should provide about half the power needed by the fridge for a whole day. That would double the run time of the storage battery.

This assumes a 6 hour sun charging time and you would likely have to re-aim the panel once or twice during the day, after the morning start position.

This also assumes the fridge cycles on about half the time. This will vary depending on how warm it is inside the van itself.

So during the 6 hours of sun the panel would spend 3 hours running the fridge and 3 hours charging the battery. That 3 hours of charge would become 6 more hours of fridge operation at the same 50/50 running rate. So 6 hours of sun would take care of about 12 hours of fridge. The next 12 hours would have to come from the battery. Then the sun would be back. So 6 hours of sun gives 12 hours of fridge time out of every 24 hour day.

These are rough numbers but they imply that 100 watts aimed for best sun in 6 hours would meet the 24 hour needs of the fridge.

Mark

WestyDreamer wrote: Maybe I should have been more clear about me Question.

My thoughts and Question was asking more about the smaller Wattage Panels.

My Hope was going with the Smaller size 50 Watt Solar Panel. They are only about 2'x2' square and thought that I could use it in multiple locations, luggage rack, poptop, etc ways once onsite and move it about into sunny areas etc by use of a interchangeable longer power cord.

But my question is would it add enough ah's back into my battery to supplement my needs. Which are manual.

If enough sunlight I don't see why not. Besides with this approach I have control over the panel Location / position..

Besides my friends who have the larger panels often don't have the portability of moving just there Panels to gather sunlight angle without re-positioning there campers once or twice and sometimes they don't have that opportunity so those huge panels are only performing like a much smaller panel anyway.. Also have seen many Panels hard mounted that once the Top is Popped the Panel was facing everything but the Sun. :oops:

Think I'll give the smaller Panel a try, going to mount the charge controller in the Van so heck I can always swap out the Panel if under performing. I'll let you know how it works out..
.

kourt Tue Jun 10, 2014 1:56 pm

I've got a Renogy 100 watt panel mounted on the pop top roof:

http://www.thesamba.com/vw/forum/viewtopic.php?t=582511&highlight=

Look through the post for more info about the special mounting hinges used on this panel to make it dismountable, with extension cord, for placement in the sun while the van is in the shade.

Here's my rig, charging on the beach this past weekend:



We basically ran the stereo, lights, Truckfridge on its highest setting, phone chargers, iPad, wifi, LED christmas lights, ham radios, and anything else we wanted for three days with no fear of depleting the 165ah house battery bank. The bank was recharged each day with ambient sunlight. In this photo the van tailgate is pointing south. We probably could have oriented the panel for more efficiency, but it wasn't necessary.

The panel mount is solid and doesn't rattle. It appears permanently installed to the casual observer, but can be removed with a little effort and knowledge.

kourt

PDXWesty Tue Jun 10, 2014 2:02 pm

You can also store the panel flat in the upper bunk. I take a 125w panel with me for use and can move it around in the sun. or mount it on top when convenient. Don't make your cord longer than 25' or you start getting too much voltage drop. The folding 100w panel is only $169 when Solarblvd has them in stock. If I were to do it again, I would get an 80-85w panel that would lat flat across the bunk with the bed either folder up or down.

You can have the bunk folded down with the pop top closed and you get quite a bit of flat storage up there. I think 50w will be too small for you.

Here's some inexpensive 60w-80w panels for about $90: http://www.solarblvd.com/Solar-Panels-&-Systems-12-Volt-Solar-Panels/c1_269/index.html

richardm82 Tue Jun 10, 2014 2:44 pm

I'm picking up one of these this week.

http://sfbay.craigslist.org/sby/ele/4504791405.html

Timwhy Tue Jun 10, 2014 2:59 pm

I think everything plays into what your needs are and have much sun shine you can receive, not mention your battery capacity.
My set up includes 135 watt panel on the roof and a 100 watt foldable panel. Recently added 100 ah battery to the
battery bank to get to 234 ah's. The sun is not cooperating with us here in the NE so more capacity is needed.

WestyDreamer Wed Jun 11, 2014 6:39 am

Ohooooo you guys are driving me insane. Guess my brainfart of trying to go small say 50 watt panel just ain't going to be practicable.

So looks like I have to take your advice Luke and look into the larger 100 gig-a-watt Panels. Problem now becomes transporting and storage of the larger panel the one I'm looking at is est size 47"x21" which should just fit across westy cargo box. Wish I could find one slightly smaller say est 46x19 as it would drop down inside of the Cargo box. Also wish I could find the larger Panels with the Blackened anodized Frames like the smaller units have just hate that bright alum frames saying hey look at me..

This is the Blackened Frame 50 Watt Panel I was considering, just wish I could find one similar in a larger panel. Renogy uses 2 of these Panels in there 100 watt portable kits.
http://www.ebay.com/itm/161277881429?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

But I don't want a potable foldup panel that I would set out on the ground and might go missing or damaged by kids playing ball etc in the camp grounds.

Guess I'll have to get creative and make the 100 watt Panel tiltable to capture sun angle. Or even removable / extendable with a length of jumper wire to capture the best sun.

One reason I liked the 50 Watt Panel was because it has the Black Frame which I can not find in anything larger like 100 watt..

Also gots another confusing question about Charge Controllers.
Example what charge voltage would the typical 10amp PWN provide?
Are they are equal or are some better then others.
What's good, what should I stay away from?
.



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