Yeah I always figured the rule of thumb was around 1 kw of energy per square meter of sun light. Of course that changes based on various conditions etc. But if THAT does not melt snow (which it does not, hence why snow stays on the ground) then it means I need more than that to melt snow on the panels. Though think I will indeed experiment with heating 1 panel at a time using a couple kw of ramped up heat. Since I only need to melt under the ice and not the entire ice maybe it is indeed doable. Something I can experiment with next year. If this works and my only limit is battery capacity then suppose it's not a big deal to get like 4 or 8 golf cart batteries in there. Can never oversize a battery bank, in fact for solar it's probably better, since if I'm always riding on 90%+ capacity it means they will last longer.
We have actual sun today - like actual direct sun light, which is very rare. I went out a while ago to clear off the snow from overnight (still crusty snow left over, just skimmed the top soft snow) and I'm actually getting around 5 watts which is not bad considering they are pretty much all covered. It's at least enough to put a bit of charge in the battery. With this sun light, maybe it will indeed cause the panels to heat up and then start melting the ice.
But yeah think for a small array of this size where I don't have much property to do anything special like a ground mount setup that is tilted better, my best bet is to probably just experiment with ways to heat them. Whether I do backfeeding, or put some nichrome wire on the back. What is the best way to insulate nichrome wire, is there any kind of sleeve that is meant for that? I'm thinking next summer I will look into putting nichrome wire on the back of the panels and then I can switch them individually. I still need to design and build the control system anyway, like I want a voltage monitoring system and energy tracking system and what not, just have not gotten around to doing it. I can do the heating with that system too. Basically just have a bunch of relays controlled by arduino. Will do outside lights and stuff too.