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Question about discolored cells

Zz1049

New Member
Joined
Jun 18, 2022
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10
Hello there all,

I purchased a 240W Newpowa solar panel and noticed some odd discoloration as well as what seems to be at least for me a manufacturing defect.

Since there are people here who have a lot of familiarity with a lot of panels, common issues and wear and tear experience I wanted to get people's takes on whether or not this is kosher to receive as a "Grade A cell" panel.

The two defects to be noticed are:
I've seen over 160 (4 panels, 40 per panel) of these solar cells and noticed only one that had this odd pattern in the middle has anyone noticed this before? Does anyone have an answer as to why this might take place?

The second defect is across the board for pretty much the entire lot of 160 cells in that there is significant whitening towards the edge of the cells typically in One direction and some cells do not actually have this defect it is kind of inconsistent to what degree but across the board something that can be seen on all of their cells.

https://photos.app.goo.gl/W7ptub7vws5aCZ3DA
I included very high resolution photos so you can see the details clearly.

I will attach them more disturbing of the discolorations in the forum image upload by cropping out the portion that is most significantly affected.

Edit: I sent the photos that I had to NewPowa and received the following rather unhelpful reply: "The basic component of a solar cell is pure silicon, a product by nature. The different color shade of silicon is caused by nature. Here is a link for your reference. https://sinovoltaics.com/quality-control/grading-of-solar-cells-a-b-c-d/ According to this article, the solar cell color discoloration usually refers to the yellow color in the solar cell. We are proud that we provide the best customer services to satisfy our customer demand. Thank you for choosing Newpowa as your preferred solar provider. Please do not hesitate to contact us should you have any further questions or concerns. Best Regards, Newpowa Team G."

They like to keep referring to their warranty however at the pace that solar panel companies come and go it really doesn't impress me that they're trying to fall back on a warranty that I might not be able to claim when the time comes let it causes an issue with function as the company would likely be gone.

I look forward to hearing about common experiences regarding this if this is something that is absolutely unacceptable or if this is just something that is typical. At the cost of $300 for a 240-watt panel I think that if being advertised as grade A solar cells they should be completely consistent across the board however I look forward to hearing people's experiences thoughts and responses.

Cheers
 

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If I had a questionable panel like that, and received that response from the seller, I would just nod my head, say 'ok thanks for your help'.

Then just to make sure the issue doesn't affect performance, I'd check the panel output against a few other of the known-good looking panels (to get a baseline), and confirm if it puts out the same power as the others. If it did, I would just roll with it and call it an aesthetic defect and trust that it will work fine...

If the panel had some kind of performance anomaly in comparison to the others, you would then have enough evidence to pursue warranty claim and get a replacement early on (while they still carry them).

I would put 2 panels side by side, at same angle, same sun, no shading, measure Voc without anything connected on each cable, then using a DC amp clamp current meter (clamped around a cable on the panel), then plug the 2 leads + and - into each other to short the panel, and measure the Isc under short-circuit. Then use a couple other known-good panels to confirm a good baseline, and hopefully you can get a good enough idea from that, if the performance of the defective looking panel is up to par on performance with the baseline.

That's just how I might approach it, others may have other suggestions as well.
 
Yeah I got a pretty decent response from someone who actually I've seen post on this forum. I'll post at the end of thread. Pretty reasonable, I appreciate your suggestion on ensuring quality performance, I actually can test 2 other identical panels of very close age so I'm going to likely do that when I get a chance to test since that will be fast as I also have 2 identical in line trolling meters x2 to live comparison. Once I mount this in the 3 panel array I'll do these tests as angle will be as identical as possible. Thank you for your feedback it's super practical and I'll definitely be referring to your post when I'm testing!

I'll post the Reply from Newpowa below:

"For me this is a scientific analysis, I would probably need to spend a week to dig in so I can put up an research paper with equations and calculations for you. Despite that I have bachelors with ME.

Since we only manufacture panels, honestly the solar cells industry is not in my knowledge. We use cells from top tier manufactures. For us, output and internal cracks are the most important things for a cell. But of course we are human we judge things by the outer appearance.
What we know is that each batch has color differences, not to mention different batches, we use color identify machine to pick and separate the solar wafers with obvious color difference.

I did spend a few hours already and right now it’s 2pm in CA and trying to gather all the informations so I can explain this. I will share you the links that I found worth the time to read.

One important thing is, most uniform colors u have seen are dying and coating, which will reduce the power significantly.
https://palmetto.com/learning-center/blog/colored-solar-panels-are-black-blue-the-only-options
‘Solar panels are black and blue because those are the natural colors that silicon becomes during the manufacturing process. ‘
We call it pure silicon but actually it’s a 98% pure SI. With other compound the color can be different
‘The 99.9999% pure SI still isn’t ready for mass production.’
https://sinovoltaics.com/learning-center/solar-cells/silicon-si-solar-cells-produced/

I would say the texturing process is the main process which will cause different colors, different angles and light absorption rates.
https://m.youtube.com/watch?v=fZ1SC-vUe_I

I have been working with this company since 2014, sold more than 20million worth of solar panels and you are my first client that using a camera to check the cells. I like your adventure spirit which can help me to learn more.

The B grade has obvious discoloration visually, not with camera. In the link from my colleague, if u enlarge the picture from the displayed “grade A” cells, u will notice obvious darker and lighter blue across the whole cells. It has clearly stated tiny color deviation is permitted. And no cameras was instructed.

If there is any issue, we just replace it for free. For consumers, quality is very important, but warranty is the insurance for quality.
If u are 10ft away from the panel and the color difference makes you uncomfortable, please do not hesitate to return the products at no cost. It’s a consumer products when I do shopping if I don’t like it just return it.

You may also purchase a panel from different brand and do the comparison, but since we have been back and forth for a while. Please do a long term review and see what we can offer in years. We have seen so many brands on eBay amazon come and goes.

Best
Jarad"
 
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