2 Portable Solar Systems

[Ag&Au]

I think the wires need to be the same length, because if they are of unequal length, there is a small but definite chance that the solar karma of the panels could become 180 degrees out of phase. This would cause them to start disliking each other and refuse to work together. At least that's what MY sources said.

Ken

[Ag&Au]

Originally Posted by Ziggy2

Yes, sounds weird but I talked with either the charge controller people or the Sanyo people and some others and they all concurred that it was optimal for performance to have the cables the same size. I have no idea why and it may make a minimal difference but I thought, it can't hurt.
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The key factor here is what does optimal mean. As Lew stated, if the cable is of sufficient diameter, then any deviation from optimal will be infinitesimal. However if it makes you feel better, knock yourself out getting them exact. Just make sure the wires are at the exact same temperature when you measure and cut them.
Ken

[Ziggy2]

Hey, I didn't come up with this. Sites like cleangreenenergyzone.com say things like this " Q: Is the length of the cable important when connecting the solar cells?
A: The cables should be short enough and have the same length." It can't hurt


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[scamp]

Originally Posted by dznf0g

So when they say up to two more can be added, they must require a different controller?

If you look at the go power web site under accessories or expansion kits you have to read between the lines because what there saying for expansion is the portable 40,80 or120 watt is the expansion to your already permanent solar panels on your trailer. And all three kits have the same 10 amp charge controller( not the greatest PWM) a much better charge controller would be a mppt charge controller but this would drive the price up, the mppt charge controller would harvest up to 30 % more power out of the same solar panels.

Don

[Ag&Au]

Originally Posted by Ziggy2

Hey, I didn't come up with this. Sites like cleangreenenergyzone.com say things like this " Q: Is the length of the cable important when connecting the solar cells?
A: The cables should be short enough and have the same length." It can't hurt

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I'm a sorry, but even after extensive rehab, I am still an incurable smart-ass. I just find it annoying when authorities, such as you quote, give a blanket -one size fits all- answer without explaining what other variables can effect the real answer to a question. For instance, using their apparent emphasis, if the cables were of different diameter then they should be of particular unequal lengths. In your case making the leads the same length may be no big deal. However in a different situation the possible mounting options might make it a PITA to make one wire unnecessarily long just to satisfy their made up equal rule.

Ken

[MaineStreamer]

I have been pondering portable solar panels for a few months, reading discussions like those above. At my introductory stage, I just want a suitcase kit that I can connect in the sun in a few minutes. It sounds like several members of this forum have been happy with 80 watts, but it might be most efficient to buy a kit that provides 100, 120 or 160 watts. Assuming that each kit is truly complete, perhaps except for addition of a longer extension cable to allow more flexibility to position the panels in the sunlight, the top choices seem to be:

RenogyⓇ Foldable Solar Suitcase Battery Charger 100W
Buy new: $269.99
3Used & newfrom $269.99

Go Power! GP-PSK-120 120W Portable Folding Solar Kit with 10 Amp Sola…
Buy new: $623.95
13Used & newfrom $543.99


Zamp Solar 160 Watt Portable Ch...Zamp Solar 160 Watt Portable...Zamp Solar 160 Watt Port...
$755.00
Solar DealzSolar

Zamp Solar 160 Watt Portable Charging System $755.00
Solar Dealz
Great for dual-battery banks / moderate users

or
Zamp Solar 120 Watt Portable Ch...Zamp Solar 120 Watt Portable...Zamp Solar 120 Watt Port...
$627.00
Solar DealzSolar

Granted that shopping more websites of additional vendors might shave a few dollars off any particular kit, it seems like a huge jump in price from the Renogy 100W kit at about $270 to 120W kits at approx. $625 or 160W kits at approx. $755. To increase from the Renogy 100W kit to the others more than doubles the price. The kit prices seem to increase exponentially with increased wattage, rather than linearly. Perhaps that is appropriate; I don't know.

Please comment on the "value" and "cost effectiveness" of these comparative solar panel kits. I am a newbie so I don't really know what demands for power I will have, but I just want to get a good value for battery charging capability with easy, non-technical set-up that I can easily carry in the Airstream while driving. It seems like purchase of a Honda EU2000 generator may be a good idea sometime too, but I would prefer to start with solar, so will wait until I have some Airstreaming history before adding a generator, if I ever do.

I welcome any advice and comments.

[AWCHIEF]

The Renogy system listed seems to be one of the better portable set ups on the market. Reviews are overall very good and it has a very competitive price.

[gandttimes]

If it has any bearing, I got 3 100W flex panels from Renogy.
The folks there were great to deal with and the panels are working as advertised.
I would have no hesitation in buying there again.


George

[MaineStreamer]

George, Did you buy 3 stand-alone panels and buy a separate controller, then hook them up together yourself? Or 3 of their suitcase kits?

[gandttimes]

I bought 3 stand alone panels. I have a Trimetric monitor inside the bedroom cupboard, and a SC2030 solar controller with temp compensation close to the batteries with a lead going out that I connect to 20 ft of #6 welding cable that hooks up to a plug in at the back of my truck as I have the panels on my canopy roof so I can position the panels where they are most effective.
You could probably do the same thing with panels placed on stands.


George