Stationary vs. Mobile panels

[Michelle (GMC Gypsy)]

I just talked to a solar company here in Albuquerque and they were telling me that the panels they sell are not designed for mobile applications because they're glass, couldn't handle the vibrations etc. He suggested I go to an RV place... I DO NOT want to deal with a place that specializes in RV stuff cuz I KNOW they'll charge way more than anything should actually cost just because they SPECIALIZE.

He did tell me that new panels should cost $1.06 per watt.

I looked at and measured my roof and I know I have plenty of room for up to a 315 watt panel (2 actually, but start at what I can afford). My question is: Are your panels specifically made for mobile applications or are they just regular house panels? Was he bullshitting me cuz he didn't want to deal with such a small scale sale?

 

[TMG51]

I'm not sure if he was bs'ing you or not but the price he gave you is right. If you're able to get something shipped, I've been very happy with Renogy. If you're stuck with a brick and mortar retailer then it's going to depend on your area.... Quartszite for example, or anywhere known for RVs, will have ample options for panel sales. If you're in a high brow area then yes an RV dealer is likely going to want to charge you a ridiculous fee. Also check Craigslist.

 

[GotSmart]

In most cases, a panel is a panel.

Renogy, like just about everyone else, uses laminated glass.  A good percentage of the panels used by the members here are Renogy.  I have 2 on my van.  

Check out Bobs store.  Renogy panels are part way down the page on the right hand side. 

http://www.cheaprvliving.com/cheap-solar-living-store/

 

[highdesertranger]

most panels are glass, except for the flexible ones and a few others. highdesertranger

 

[Spaceman Spiff]

I have 2 X 100 watt rigid (glass) Renogy panels on my camper for 2+ years with no problems.  And I have traveled on some pretty bad washboard roads!  I doubt you will get worse vibration than that.

IMHO, smaller panels give you more flexibility in configuring than larger panels:

 -  Smaller panels will be more rigid than larger panels (less span between frame rails).

 - If one small panel is damaged, you can disconnect it and continue on.  Damage a large panel and it may or may not work, but you cannot disconnect the damaged part and use the rest.

 - If one small  panel is shaded (and panels are connected in parallel) the others will continue to generate power.  If a portion of a large panel is shaded, the output of the whole panel is degraded and possibly eliminated.

  - Most larger panels are higher voltage, necessitating MPPT controllers and you must match voltages when adding panels; can't add a 12 volt panel to a 24V or 36V panel (although two 12V panels connected in series can be connected in parallel to a 24V panel).

 -- Spiff

 

[Michelle (GMC Gypsy)]

I have 2 X 100 watt rigid (glass) Renogy panels on my camper for 2+ years with no problems.  And I have traveled on some pretty bad washboard roads!  I doubt you will get worse vibration than that.

IMHO, smaller panels give you more flexibility in configuring than larger panels:

 -  Smaller panels will be more rigid than larger panels (less span between frame rails).

 - If one small panel is damaged, you can disconnect it and continue on.  Damage a large panel and it may or may not work, but you cannot disconnect the damaged part and use the rest.

 - If one small  panel is shaded (and panels are connected in parallel) the others will continue to generate power.  If a portion of a large panel is shaded, the output of the whole panel is degraded and possibly eliminated.

  - Most larger panels are higher voltage, necessitating MPPT controllers and you must match voltages when adding panels; can't add a 12 volt panel to a 24V or 36V panel (although two 12V panels connected in series can be connected in parallel to a 24V panel).

 -- Spiff

Ok, that makes sense. So maybe start off with the 200w suitcase and add 100w panels to the roof later. I assume you can connect it all to 1 charge controller?

 

[rvpopeye]

As long as the panel(s) total output amps is less than the controller max input amps.

 

[GotSmart]

Ok, that makes sense. So maybe start off with the 200w suitcase and add 100w panels to the roof later. I assume you can connect it all to 1 charge controller?

As long as the voltages are the same, and the CC is designed to take it.

Just a warning.  Panels can put out more than their ratings at high elevations.  Always get a controller that can take more than your panels are supposed to produce.

 

[WheelEstate USA]

I quickly got tired of dealing with portable panels and went with roof mounts on a ladder rack. There are places where it isn't good to set out a suitcase unit and mounted panels are at work all the time, even while driving.

 

[29chico]

If you go with a PWM controller you have to make sure that you don't pump too many AMPS thru it from the panels.

If you go with a quality MPPT controller you must be careful about not exceeding the maximum VOLTS open circuit (Voc) rating of the controller.  To illustrate this fact Morningstar allows their MPPT controllers to be used to charge a low voltage battery bank from a higher voltage battery bank.  A large high voltage battery bank can act as a nearly unlimited current source for a short period of time.  Trying to charge a low voltage bank from a higher voltage bank with a PWM or even McCheese MPPT controller would be dangerous.  For a better understanding of this you could google: current limiting device  .

Either way, a solar panel at high elevation, in bright full sun in cold temps is the perfect storm to produce way more AMPS and VOLTS than it is rated at.