1 Large vs 3 small panels?

[GoingMobile]

Looking at Solar Panels, various brands but keeping an eye on Renogy.

I can get a 320 watt panel that has a footprint of 65.6" x 39.5" weighing 40lbs for $346. ordered through Home Depot with free shipping to the store for me to pickup.

Or I could get 3 100w panels with a footprint of 42.2" x 19.6, weighing 16.5lbs each. for $103.00 each.

Or 2 x 200 watt panels with a footprint of 63.8" x 25.9" weighing 25lbs each for $275. each

The roof rack on top of my van I will mount them to measures 66" across, A couple of 14"x14" roof vent fans front and rear. Could easily fit the 320 watt panel across a space in the middle. I'm leaning towards that as it seems the simplest solution that actually takes up the least amount of rack space.

I could see an advantage to more smaller panels if I were trying to work around a lot of other items mounted to the roof, but that is not really the case.  I'm wondering if there are advantages of multiple, lighter weight, smaller footprint (individually but not as a whole) panels on the roof of a vehicle?

Would larger panels be more prone to get damaged on a vehicle roof? Could the all of your eggs in one basket be a potential problem? Any electronic reasons for connecting smaller panels rather than one big one?

Or should I just go ahead and mount the 320 watt panel and be done with it?

 

[skyl4rk]

One advantage of smaller panels is that if one gets partially shaded, the other two will still put out full voltage. However, I would probably go with the larger panel to reduce cabling and rack mounting hardware.

 

[PlethoraOfGuns]

Pros and cons any which way you slice the cheese. I would do whatever makes the most efficient use of rooftop space to get the most wattage in your array.

 

[jonyjoe303]

I would go with one larger panel, I got a 365 watt panel (77"x39") on my astrovan and it takes up most of the space but having one panel is easier all around.
Weight is in the 50 lbs, but I was able to install it on my own, I didnt even use a ladder.
Performance is excellent with mppt I was getting up to 15 amps in winter, now that summer is almost here I seen it peak at 23 amps.
If you need to, removed the covers on the roof vents and just place the panel over them, that what I did on my installation. I got 4 roof vents, the panel goes over them. The panel will keep the rain from going inside your van. I wouldn't let the roof vents dictate where the panel goes.

Picture of the 365 watt panel next to the one I replaced 240 watt.

 

[jimindenver]

Chose the option that gives you the most watts.

 

[Cammalu]

Santan has 250 watt solar panels for $50.

 

[Camper]

If I could find a 365-watt panel at a reasonable price without paying expensive truck freight, I'd buy it today.

 

[MrNoodly]

Fewer panels = simpler cabling, no junctions.

Fewer panels = simpler mounting

 

[abnorm]

LOCATION Location location......................Camper....Going Mobile.....Where are you......

 

[Camper]

Probably 5-days from a 365-watt solar panel.

 

[abnorm]

A new member just posted he has used panels For Sale in Albany N.Y.

I bought my B-grade panels Cheap in Miami Gardens Florida

And of course San Tan Solar in Gilbert AZ

 

[GoingMobile]

One thing I had not noticed or considered; The larger and higher wattage panels are 24V and the smaller panels are 12V. I have to admit I don't know how this factors in. I'm guessing the solar charging controller can handle either? If I started with the 24V could I add smaller 12V panels later?

 

[abnorm]

No .......................you can not mix different voltage panels on a single controller

 

[B and C]

A MPPT controller will make the most use of any panels you throw at them as long as it can handle the amperage.

And NO, do not mix panels on the same charge controller.

 

[ForestRoadSurfers]

The important readings to know to size your system is your mppt/generators max input amps and Open Current Voltage, 12v/24v/48v doesn't really factor in if you have a good mppt

I got my panels from San Tan Solar for less so check em out online.

 

[ldsreliance]

If it were me I would go with the three 100W panels.  That would allow you to wire them in series for 36V and minimize voltage drop in your wiring.  That will give you the flexibility to make longer wire runs if you need to and use more affordable sized cables.

As has already been said a few times, if you get a quality MPPT charge controller it will handle the increased voltage easily.