I'm not seeing those prices so I'll keep looking. I also like the idea of bi-facial bc I assume reflection of sunlight off the water adds watts. Is that how bi-facials work, or am I assuming facts not in evidence?
Thank you.
Just search for panels on google - don't buy "marine" panels, or rely on marine retail stores for them. Here is where I got the bifacial ones I mentioned we have now:
https://www.platt.com/p/2174312/hyundai/solar-module-410w-66-cell-b-b/hynhiss410yhbk
You can find larger ones cheaper like here:
JA Solar 16BB N-type Solar Panel Bifacial 580w 575W 570W Solar Energy System
Solar is very cheap right now. If you pay more than 50cents/W, you are getting a bad deal.
Yes, bifacial panels work by harvesting reflected sunlight on their backsides. However, it isn't like having two panels in one, and water isn't a good reflector of sunlight.
We had for several years two 400W panels from the same manufacturer next to each other on an arch overhanging the water. One panel was a traditional one, and the other was that exact panel only bifacial. While we would on occasion see up to 35% extra gain from the bifacial, the overall yearly average increase during all conditions of the bifacial panel over the non-bifacial was 12%. This could even be measured instantaneously by placing towels over the tops of the panels, when one panel would stop producing, while the bifacial still produced current.
So they do work to harvest more light, but don't expect miracle production. However, 12% on average is significant. It turned that 400W panel into a 450W panel for no extra money or space.
Our bifacials (we now have four of them) are mounted over the water on an arch. You would think water is a good reflector of light since it blinds you, but it actually is very poor at that. Ironically, we get more output from the backside of our panels when the dinghy is in the davits blocking the light from the water, but reflecting light from its white floor and grey tubes. I've toyed with the idea of throwing a white sheet over the dinghy, or putting a reflector below the panels.
Mark