PV panels, Photovoltaic, testing and running broken ones.

[clockmanFRA]

August 2021. . PV panels, Photovoltaic, testing broken ones.

Out of our 61 large PV monocrystalline panels, large being over 1 meter x 1.6 meter, we have 2 that have been broken and shattered.

All PV panels, the ones i have, use hardened tempered glass with the silicone cells and connections fused to the rear of the glass and then vacuum sealed with a membrane on the rear then sealed into a aluminium frame. PV panels produce DC, (direct current), and are connected in series to increase the voltage but the amperage is held to the lowest amperage rating of the connected PV panels string.
 
As you can see in the photos the glass just shatters.





No 1 Photo, .......... The first is a budget/cheapo KNIVE 250w, 1 meter x 1.6-meter, Mono, made in China, been on the static array over 12 years now. Failure due to faulty manufacturing on the rear film and the heat has buckled the glass and as it is hardened it has shattered. Been through one winter so far and no loss of electrical voltage but the amperage is dropping.
Eventually the static array will cease generating as the panels are series connected and the water ingress gets in and shorts the PV panel out. But for now, i will let it run and monitor.





No 2 Photo, ......... The other is a SOLARWORLD 260w, 1 meter by 1.65 meters, Mono PV panel, and made in Germany. All parts were made in Germany under EEC regulations. And this a good reasonable quality panel.
It was hit by a flying stone sometime in early 2019, it is still producing electricity at good voltage and good amperage.

I have swapped this broken one from the 4.75KW roof array, for another good SOLARWORLD and now installed the broken one into the static array for close observation and monitoring.
Time will tell how these two broken PV panels behave.

My thanks to Christopher and also Peter for their assistance in the swap outs and re-installation.

[OperaHouse]

Haven't had one shatter yet.  I have been hit by lightning and have blown holes thru the back. Some still work, one has had water enter thru the back where it blew a hole thru.

[clockmanFRA]

Thanks OperaHouse,

Crikey, lightning strike well that's a new one for me, as its normal in Europe for the Array metal frame to take the hit.

Your comments are very useful.

I am interested in seeing how long the panel is effective in a string, depending on its damage, and how long they carry on producing power at what drop off rates.

[OperaHouse]

I just bought another KW, 4 panels.  They were real cheap and supposed to be new old stock Trina. I didn't look at them too closely. Later when I cleaned them up I noticed there were hot spots, like you used to see in the very olden days on cells. 4 to 17 each panel.  And these were on the parallel side of the adjacent cell as if there was an arc.  These marks ONLY happened in pairs.  These panels were were then mounted next to identical panels. I looked at the existing panels and they had the same spots. Those had gone thru the same event except the array which had been hit was 20M away. I'll have to get up on the roof and get a picture.  hat event was years ago and they still work.  I had to replace a number of bypass diodes on that array.  Cheap low voltage diodes saved the panels!

[clockmanFRA]

OperaHouse,

Here is the back and front of the cheapo KNIVE Mono PV panel.

As you can see its just one cell that has shorted out after having an internal fault