Module discoloration

[electrofelon]

Lots of these discolored areas on my solar array. What do ya'll think of this? Ever seen this before? Is it bad sign?

 

[solarken]

It is hard to tell from the photo but I don't recall seeing a similar color/pattern like that. Looks blue from the photo. Did you try reaching it with a wet broom to see if it is just surface discoloration?

 

[electrofelon]

It's definitely under the glass

 

[PaulMmn]

How's the power output from the array? Can you check the individual panels??
Any possibility there's water or condensation getting under the glass?

 

[Elect117]

It looks like either some kind of water damage or heat damage.

 

[ptonsparky]

Better yours than a customers, but then I’d be looking back on any I’d sold.

 

[electrofelon]

How's the power output from the array? Can you check the individual panels??
Any possibility there's water or condensation getting under the glass?

The system has string inverters so no module level monitoring. It would be super easy to just short the leads of a discolored and a non discolored one and clamp it and compare the values Overall output seems to be fine.

 

[jaggedben]

I would say it's a bad sign. How bad is hard to tell. Haven't seen anything exactly like that myself.

 

[jaggedben]

What do the bottoms look like?

 

[electrofelon]

What do the bottoms look like?

Everything looks normal from the back. I did not use a thermometer, but temperature feels all uniform at the back.

A friend and I went in on these panels together, I will look at his and see if he has the discoloration too.

 

[PWDickerson]

Are you sure it isn't mineral hardness on the surface of the glass? Wipe an area down with vinegar and see if it can dissolve it.

 

[Fred B]

Any loss of power output? Looks typical of separation of glass surface from the substrate below, potentially allowing air or liquid into the space. Seen that type of de-lam on other stuff but might be first for PV.

 

[ggunn]

It could also be a light refraction effect that has no impact on module production.

 

[gadfly56]

It could also be a light refraction effect that has no impact on module production.

I suppose it's possible, but the irregular shape and sharp boundaries suggest something physical is going on. I vote for delamination and water intrusion.

 

[ggunn]

I suppose it's possible, but the irregular shape and sharp boundaries suggest something physical is going on. I vote for delamination and water intrusion.

It may not be a problem. Glass is somewhat permeable to O2 and Si forms a thin SiO2 layer when exposed to O2. That could have refractive index effects (like oil sheen on water) that would not affect production. Can you see me waving my hands around?

 

[bbcleanenergy]

I have seen similar looking modules when a customer tried to wash their modules with soap and did a poor job of fully rinsing them off.

 

[electrofelon]

Are you sure it isn't mineral hardness on the surface of the glass? Wipe an area down with vinegar and see if it can dissolve it.

I have seen similar looking modules when a customer tried to wash their modules with soap and did a poor job of fully rinsing them off.

It is definitely under the glass.

I suppose it's possible, but the irregular shape and sharp boundaries suggest something physical is going on. I vote for delamination and water intrusion.

The back sheet appears to be perfect and undamaged. I agree it looks like some sort of oxidation or corrosion, but they're absolutely no signs of a sealing failure.

 

[electrofelon]

Look at the module in picture SP2 and sp3. There are some interesting things to notice. One is the squarish normal spot in the top middle. Also look at the upper right: there is a interesting circular spot.

 

[jaggedben]

I was wondering if the circular spot was related to a suction cup being used at some point. Maybe during manufacturing or maybe later.

 

[electrofelon]

I was wondering if the circular spot was related to a suction cup being used at some point. Maybe during manufacturing or maybe later.

That is what I figured, it was during the manufacturing process.