Series string shading summed up in 4 pictures

[PreppenWolf]

I know zero about tigos. I clearly need to investigate this being in the northeast.

 

[Lt.Dan]

Looks nice. What's the bare minimum Tigo equipment you need to get the neat monitoring software going?

You'll need a TS4-A-0 for each panel you want the optimizer on, then 1x Tigo Access Point (TAP) per 300 Optimizers, and 1x Cloud Connect Advanced (CCA) per 7 TAP's.

I have 44x Optimizers, 1x TAP, and 1x CCA.

 

[Lt.Dan]

If my math is correct, the 7kwh gained with the Tigos roughtly cost around $0.35-40/watt? Cheaper than adding more panels, right?

Yes, roughly $0.40/w. Its a bonus point if you are like me, and don't have anywhere to PUT more panels. This makes more power with the square footage you already have.

 

[cs1234]

You'll need a TS4-A-0 for each panel you want the optimizer on, then 1x Tigo Access Point (TAP) per 300 Optimizers, and 1x Cloud Connect Advanced (CCA) per 7 TAP's.

I have 44x Optimizers, 1x TAP, and 1x CCA.

Is there any monthly charge for the software access?

 

[wattmatters]

You would think that the bypass diode would do a better job on either string, but it doesn't.

How long have those end panels had to deal with such hard shading?
It places extra stress on the bypass diodes. Perhaps they are toast?

It's worse in the afternoon actually. This array pulls a substantial amount of power. Most useful irradiance for PV occurs when sun is high above. So I'm not losing much over the course of a day.

Does the array supply close to its full rated power (~3.9 kW) in good conditions?

Some thermal imaging perhaps, or other testing of the end panels to check their condition would be interesting.

 

[Lt.Dan]

Is there any monthly charge for the software access?

No sir. I haven't paid a dime.

 

[Danke]

Yes, roughly $0.40/w. Its a bonus point if you are like me, and don't have anywhere to PUT more panels. This makes more power with the square footage you already have.

Is that right? I’m paying around $0.12/watt for RSD/Optimizer.

 

[Zwy]

Would be nice for someone to post their evidence of series string being better than parallel configuration for shading. Please challenge my position! I have done this test many times now and the results are the same everytime. I even covered this in older solar panel test videos. Same results, every time.

In your first post, all it shows is the panels shaded in parallel only produce 200W and when unshaded the panels produced 2465W. While the parallel string might produce 200W shaded and the series string might produce nothing, if both were not shaded, the watts produced should be the same.

If there was large voltage drop (very long distance, like I cover, 420 feet one way), the series may actually perform better due to the VD and power loss in a parallel string.

 

[cs1234]

Is that right? I’m paying around $0.12/watt for RSD/Optimizer.

Wouldn't this depend on panel/string size you are placing RSD/Optimizers on? Also the cost you pay for the equipment.

 

[Lt.Dan]

Is that right? I’m paying around $0.12/watt for RSD/Optimizer.

In my case, I bought 44 optimizers, and they are $55/ea~, so $2420, and I gained 7kwh extra, so 2420/7000=$0.345. So roughly $0.35/watt, and that doesn't include the CCA and Tap, so roughly $0.40/watt.

This is in my case, for that one particular day. I'd be interested in the reclaimed power over a year.

 

[Zwy]

I wasn't clear. Just rotate the arrangement you have now 90 degrees.. So one string would have the the bottom half shaded and one string in full sun. In that scenario I think you'd get close to 75% of output of all the panels being in full sun. Saying this since you are trying to make a point about series arrangement but your current arrangement shows worst possible arrangement. With the panels you have I believe you can shade one half of an entire panel (top or bottom) and still get half the panel output instead of none like you do by shading parts of both the bottom and top of a panel.

I agree, Solar Queen did a video way back showing this. The series between the cells is longitudinal and blocking the bottom cuts all cell strings off. If the panels were rotated, the bypass diodes would actually work as intended, probably about 66% or 75% output depending on how many rows of cells.

 

[Danke]

In my case, I bought 44 optimizers, and they are $55/ea~, so $2420, and I gained 7kwh extra, so 2420/7000=$0.345. So roughly $0.35/watt, and that doesn't include the CCA and Tap, so roughly $0.40/watt.

This is in my case, for that one particular day. I'd be interested in the reclaimed power over a year.

Oh, I see. You calculated it off of gain.

 

[Zwy]

I agree, Solar Queen did a video way back showing this. The series between the cells is longitudinal and blocking the bottom cuts all cell strings off. If the panels were rotated, the bypass diodes would actually work as intended, probably about 66% or 75% output depending on how many rows of cells.

 

[Zwy]

I wasn't clear. Just rotate the arrangement you have now 90 degrees.. So one string would have the the bottom half shaded and one string in full sun. In that scenario I think you'd get close to 75% of output of all the panels being in full sun. Saying this since you are trying to make a point about series arrangement but your current arrangement shows worst possible arrangement. With the panels you have I believe you can shade one half of an entire panel (top or bottom) and still get half the panel output instead of none like you do by shading parts of both the bottom and top of a panel.

One more aspect to this, with the panels rotated 90 degrees, one panel would put out full output (not quite due to early morning but way more power and longer than the arrangement shown in first post) and only the panel shaded on the one side would have reduced output but it would still produce power, probably 60% to 70%.

 

[EastTexCowboy]

When can we expect this video about bananas driving?
Or maybe I miss read. lol

If you get shading on bananas is it worse if they are in series? Asking for a friend.

 

[solar_trees]

If you have 2 parallel strings (String A and String B) and the bypass diodes activate on one of the panels in String A, will that reduce the output of String B?

 

[timselectric]

I buy all of my bananas in a parallel bunch.

 

[timselectric]

If you have 2 parallel strings (String A and String B) and the bypass diodes activate on one of the panels in String A, will that reduce the output of String B?

The overall voltage will balance, at a slightly decreased amount. (Depending on how the panel is shaded)

 

[wattmatters]

I buy all of my bananas in a parallel bunch.

I'll hand it to you, that's clever.

 

[farmhand]

You could however arrange those strings such that the bottom half of one of the strings is shaded and you'd get much better results even under shading conditions due to that modules design (forget the term, split cell?)

Not sure if reversing diodes are in the previous 4-pages, but it's a key note I didn't learn until days before ordering the combiner box (Whew).