Partial panel shade & how much is too much?

[Gotshocked!]

I've got 2 minor shade issues. The post and the overlapped panel.

This row of panels is currently set at 45.4ish* for winter.
The post is an issue with each panel but they will be cut down all at the same height, just above the panel's frames. Still, I'll be faced with this issue again as these panels will be adjusted to 30* for spring & fall. If I adjust them for summer to 14*, the shade will be even worse.

Will this little bit of shade really hurt production?

The land is sloped, so to keep the panels level without being propped up too high, I split the 1/2's of strings. There's 13 panels in this row, 5 for strings 1 & 2 and the last 3 panels for string 3. The other 1/2 of the 3 strings will be in the longer row. I added a extra block to each side of the last panel I installed in the pics below to reduce the shade cast by the adjacent panel. I could add another, and I'll have to match what I add to the other 2 panels that make up this part of string 3. I could also add space between the row & these last 3 panels, but I don't wanna.
Will this shade coming from the adjacent panel (best seen in pic #1 & #2) hurt production?

These are Canadian Solar 400W Mono-crystalline CS6R-400MS-HL

#1



#2


#3


#4


#5

 

[sunshine_eggo]

Assuming serial wiring is horizontal, i.e., shading from top or bottom activates bypass diodes.

As pictured:

The overlap will likely cause about a 15-20% decrease in output from the whole panel and may affect all other panels in series with it similarly.

The vertical between probably about 20-25% of 1/3 of the panel or the whole panel and may impact all other panels in series similarly.

I don't even want to talk about the heavy shading on 1/2 of the array.

Shade, full or partial can be devastating.

I made my panels 3 position adjustable for Winter, summer, fall/spring. Never changed them once in 3 years. Found it wasn't worth the effort. Summer - panels are hotter, so they're less efficient even when getting more sun. Winter? Panels are colder, so they're more efficient even when getting less sun.

Eliminate all shade possible.

 

[kayakingphotos]

Any shade won't help. Can be hard to know if it will be a 1% reduction in power, 5%?, 20%?

Have you seen Dave Jones video of his shading issue from a few years back?

 

[Crowz]

I'd cut the post in half if not a bit below the lowest point they will be at for summer. Then overlap the pieces back using bolts, this way you can bolt the cut off parts in place for winter settings.

 

[RoadTurtle]

really easy, measure the output of each panel with that shade. On my 5th wheel, I had one panel that had literally a corner of the panel shaded, and it literally took out 50% of that panels output. It hit the panel just right. I had another panel that was shaded by my elevated TV antenna pole, and the little tiny shadow across the entire panel, took the entire panel out of production until the sun moved enough.

 

[rhino]

Split cell modules would not be as affected. If you are installing a system where shading is an issue using split cell modules will help reduce the impact compared to "standard" modules.

 

[LydMekk]

The last panel section needs to be adjusted to the exact same height as the others, now it is further back and you can see the stripe of shade from the panels next to last.

 

[Gotshocked!]

Assuming serial wiring is horizontal, i.e., shading from top or bottom activates bypass diodes.

As pictured:

The overlap will likely cause about a 15-20% decrease in output from the whole panel and may affect all other panels in series with it similarly.

The vertical between probably about 20-25% of 1/3 of the panel or the whole panel and may impact all other panels in series similarly.

I don't even want to talk about the heavy shading on 1/2 of the array.

Shade, full or partial can be devastating.

I made my panels 3 position adjustable for Winter, summer, fall/spring. Never changed them once in 3 years. Found it wasn't worth the effort. Summer - panels are hotter, so they're less efficient even when getting more sun. Winter? Panels are colder, so they're more efficient even when getting less sun.

Eliminate all shade possible.

The picture was taken late in the day, around 4pm. The panels seem to get full sun from around 8 to 3:30 this time of year. Regardless of the season, as the sun goes down, I'll loose string 1 first, then 2 and finally 3. In those pic's, string 1 is down and string 2 probably is as well because so much of it is shaded. String 3 would still be producing though, up until around 5-5:30 maybe.

You never adjusted them once in 3 years? Please tell me what season have you left them at? Spring/fall? I might do the same, though it's a bummer because I was looking forward to maximizing their potential.

 

[Gotshocked!]

Any shade won't help. Can be hard to know if it will be a 1% reduction in power, 5%?, 20%?

Have you seen Dave Jones video of his shading issue from a few years back?

I haven't seen this video, but to be clear, I'm just referring to the little shade from the posts & the slight shade from the adjacent panel due to the slope of the property and how I've chosen to deal with that. All that shade you see in these pics is inevitable and this area gets full sun with 0 shade other than that which I've apparently created for myself.

 

[Gotshocked!]

I'd cut the post in half if not a bit below the lowest point they will be at for summer. Then overlap the pieces back using bolts, this way you can bolt the cut off parts in place for winter settings.

That's not a bad idea, but if I did that, I'd probably have to scrap my ultra-cheap solar mini field idea and spend a bunch of money on a unistrut design or GOD forbid, buy a kit. I don't think these little 4' light duty t-posts are fit to be modified much.

 

[Gotshocked!]

really easy, measure the output of each panel with that shade. On my 5th wheel, I had one panel that had literally a corner of the panel shaded, and it literally took out 50% of that panels output. It hit the panel just right. I had another panel that was shaded by my elevated TV antenna pole, and the little tiny shadow across the entire panel, took the entire panel out of production until the sun moved enough.

It's going to be a rainy few days, but when things clear up, I'm going to do this.

 

[Gotshocked!]

The last panel section needs to be adjusted to the exact same height as the others, now it is further back and you can see the stripe of shade from the panels next to last.

Yes, that's the shade I'm most concerned with. From the first 5 panels, the ones in the shade, to the next 5 there is also a drop, but a little less. The lay of the land is an issue. The panel looks further back, but in fact it's right in line with the rest but because it sits lower, shade is being cast on it.

 

[Zapper77]

In this example. I have one 4x4 post that cast a small shadow on the bottom left panel. TIGO reports a loss of 70 watts per string panel.

 

[Gotshocked!]

In this example. I have one 4x4 post that cast a small shadow on the bottom left panel. TIGO reports a loss of 70 watts per string panel.

70 watt loss per panel on that string? Looks like you've got something like 350 watt panels then, so a 20% loss?
How small a shadow was this?

 

[Zapper77]

70 watt loss per panel on that string? Looks like you've got something like 350 watt panels then, so a 20% loss?
How small a shadow was this?

Small, I'll try to get a photo tomorrow. Panels are 455 watts.