Stacked solar panels?

[Bbasso]

I'm trying to achieve a larger PV array but with a same size footprint.
I currently have two 100wt panels end to end long ways and while that's enough for most of the time, there have been plenty of times that I could have used more.

I have plans (just have to buy another kayak) so half of my roof is spoken for. But the other half is for solar stuff.

A simple question first... maybe simple?
If I have the two current panels sitting on top of an exact copy (on slides) obviously blocking the lower two will the top two exposed panel still work like before?
So my thoughts are to slide out the lower panels when parked to double my harvest.

Can this be done?
Is there any tricks to wiring this?
What are your suggestions?

If I'm not clear, let me know I was thinking about this while cooking dinner on a cloudy afternoon and trying to make sense of my thoughts while stuffing myself lol... food coma. :chef:

I appreciate your feedback

 

[john61ct]

No issues electrically, just add another controller if doubling exceeds it's spec'd limits.

If you do this please post a howto re mounting hardware.

I've considered doing something similar with "semiflex" panels mounted on thin but stiff boards, but not mounted on the roof, just stack-bundled in transit, then spread out around the site.

 

[Bbasso]

If I ever get to actually achieve this I'll have to buy a bigger SCC. Mine is the eco-worthy 20 amp and I sometimes see 16 amps off the 200watts now...
I'll have to get a 40 amp SCC to be safe.

As for the mounting hardware stuff, I'll be happy to post once I figured it out. I'm still on the thinking stages.

 

[Bbasso]

So the complete shading of the lower panels won't matter?

 

[dwh]

If you rig all the PV modules in parallel, having half the array shaded will just cut the output amperage in half. It won't affect the output voltage.

If you rig the top two in series, and rig the bottom two in series, then parallel the two series strings, same deal. Half the amps but at the same voltage.

You would only have a potential problem if you had top and bottom panels rigged together in series.

 

[PA Slammer]

First company to do a flexible solar awning wins!

 

[Bbasso]

dwh, thanks. I was a little concerned about that.

As for the awning, when I get this setup the slide out panels should provide some shade for me...

 

[Smoker]

I'm trying to achieve a larger PV array but with a same size footprint.
I currently have two 100wt panels end to end long ways and while that's enough for most of the time, there have been plenty of times that I could have used more.

I have plans (just have to buy another kayak) so half of my roof is spoken for. But the other half is for solar stuff.

A simple question first... maybe simple?
If I have the two current panels sitting on top of an exact copy (on slides) obviously blocking the lower two will the top two exposed panel still work like before?
So my thoughts are to slide out the lower panels when parked to double my harvest.

Can this be done?
Is there any tricks to wiring this?
What are your suggestions?

If I'm not clear, let me know I was thinking about this while cooking dinner on a cloudy afternoon and trying to make sense of my thoughts while stuffing myself lol... food coma. :chef:

I appreciate your feedback

See this in the Sportsmobile Forum. Very slick and sounds like what you are trying to do.

http://www.sportsmobileforum.com/forums/f24/300watt-sliding-solar-install-space-saver-18662.html

 

[Bbasso]

Wow, thanks for linking that, very very close to the idea I have.

 

[rayra]

wire the panels in parallel to the controller, not serial. So the shaded panels don't restrict anything.

 

[Bbasso]

Fantastic advice, thank you