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Will metal roof reflect enough sunlight for bi-facial panels

PoPoShoo

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Feb 3, 2022
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Our Heliene 400w bi-facial panels are mounted on a green metal roof, about 1.5-2" above the surface of roof

Could we expect any residual solar energy from reflection(s) off the roof? Guess what I'm curious about, does some of the sunlight pass through the panel glass (which then could reflect back)? Curious how bi-facial panels are supposed to be able to capture residual energy from the back side
 
Sounds sort of feasible. Doubt the installer would appreciate you buffing the roof before the panels are installed though.
Catching more light may become more popular, some folks seem to be trying.

According to this site
ecobusinesslinks.com/surveys/free-solar-panel-price-survey/

PEIMAR modules are 19.36% efficient, and can be had for $.61 watt.

Thanks to the use of PERC cells, PEIMAR modules are able to reach even higher efficiences, as they facilitate the light imprisonment in close proximity to the rear surface and optimise the electron capture.
eco-distributing.com/Peimar-SG315M-BF-315W-Mono-Black-Frame-White-Back-40MM/
 
1645462477721.pngThe lighter the colour the more it reflects back with Natural White being most efficient as it reflects the full colour spectrum.

Bi-Facial Panel mounting on a roof is not quite like a standard panel, there needs to be adequate spacing from the surface to the back of the panels. The manufacturer spec sheet should have the specs for that.
 
I recall from university, dark green absorbs more than black. Guess that makes sense. Plants and all.
 
I don't think a bifacial panel mounted 2" above the surface is going to do what you want. The number I heard for bifacial is that it should be offset from the reflecting surface by 1 meter.

From a Solar Power World article:

The higher a bifacial module is tilted, the more power it produces from its bifacial properties. Bifacial modules mounted flush to a rooftop block any reflected light from reaching the backside of the cells. That’s why bifacial modules perform better on flat commercial rooftops and ground-mounted arrays, because there is more room for tilt and bouncing reflected light to the rear of the modules.
 
WYtreasure, do you if light will actually "pass through" the glass panel?
I think you meant to ask "Do I know...". Somedays I think I know stuff, today ain't one of them.
I do know when my panels produce voltage when they are in the house with ZERO light hitting the front of the panel.:unsure:
 
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