Questions regarding adding second portable solar panel?

[BBZ]

ok.. Have 160 watts and its mostly sufficient, however, here is Colorado we need to park out of direct sun in summer months and therefore I have concluded that a portable panel with longer wiring would be ideal.

How does one set that up? Do I need a second controller or are there panels with built in chargers?

Looking for the simplest solution....

Thanks in advance!

 

[ri-f]

ok.. Have 160 watts and its mostly sufficient, however, here is Colorado we need to park out of direct sun in summer months and therefore I have concluded that a portable panel with longer wiring would be ideal.

How does one set that up? Do I need a second controller or are there panels with built in chargers?

Looking for the simplest solution....

Thanks in advance!

BBZ - basically, if you don't already have an external solar plug on your camper, you'll need to install one or find another way to run the wires from the portable either directly to your battery or to a controller. If your existing controller can handle your rooftop 160w panel and the additional voltage/current combination that the portable panel will produce, then you could use the same controller for both with a small bus bar for the two sets of wires. I'd be inclined to use a separate MPPT controller, and isolate the two different panels since they won't be identical, but that's just me. Many portable panels come with a built in PWM controller that will not require connecting to your existing controller. Those panels wires could simply terminate with an in-line fuse, or a thermal circuit breaker just before the battery. You'll probably need at least 50 feet of 8 AWG wire to get to the sunny spot and to avoid efficiency losses through the wires. And you'll need to actively move your panels to follow the sun as it moves throughout the day. It's kind of a loaded question, because there are lots of considerations and ways to go about it, but essentiallyif you are set on using a portable panel, then that's the basic idea.

Rich

 

[Vic Harder]

Rich is right, as usual. Simple can be expensive for what you get in terms of watts and efficiency. For cables, get MC4 cables that are rated for being outdoors. They are more durable and UV resistant. I had 100' for my portables, and usually wished they were shorter. Getting two sets, one 25' and another 50' would give you the option of going to 75' if needed.

Separate controller, as Rich suggested, is best. No need to worry about identical panels. Also, if you buy the panels and controller separate, you can buy a good MPPT controller vs settling for the cheaper (less efficient) PWM controllers that most kits come with.

Finally, if you have the room, consider buying two small 100W rigid panels. They are easier to support on an angle, heavier (won't blow away in the wind) and far less expensive.