Number crunching

Do the panels have any additional protection?

 

Not that I know of. What kind of protections can you install on the rooftop panels?

 

Sandwich panel

https://www.researchgate.net/figure/Sandwich-panel-structure-of-a-crystalline-photovoltaic-module-A-Single-glass_fig1_353521384

 

Thanks but it does not look like anything commercially available being on Research Gate. Even if it exists as commercial product, I imagine that would increase the cost of the panel to the point no one can afford it. Besides, the problem we just had would not be prevented by the impact resistant glass. We did not have hail, we just had freezing rain.

 

Regular ice build up might make a defrosting system worth while. Even thin, the wires will cast a shadow on the cells. Vertically mounted, bilateral panels might be a better option with such concerns. Otherwise, a deicing solution for sometimes events, as long as the chemicals won't damage to panels.

 

I dealt with snow by raking snow off the the panel with a long snow rake and wide rubber squeeze so far. But there is nothing I can do about freezing rain, especially when snow followed by freezing rain like last night event. I am not familiar with solar panel defrosting system. No option like that was ever suggested by the installer. And now, all the panels are installed on the rooftop, I don't see there is any easy and cost effective way to retrofit such system. I will just have to wait for natural warm-up. Once the day time temp hit above freezing, it should not take long for the layer of frozen ice/snow to slide off.

EDIT TO ADD: I found this site Snow melting system for solar panels | Thermaltt
Looks like this type of heating film is installed on the back of individual PV panel. I have no idea what the cost of material and installation. Maybe DIY installable looking at the video. But only for uninstalled panels. Once they are up on the roof, you can't do anything unless uninstall all the panels and do it all over again which I am not going to do.