GEAR: Lumos Solar GSX Bifi Module System

The new Lumos Solar GSX Bifi Module System

Lumos Solar ( has developed its GSX Bifi Module System, a glass-on-glass frameless module that generates energy from sunlight on the module’s face and from ambient light on the module’s back. The GSX system has integrated weatherproofing, and concealed junction boxes and wiring—key features and aesthetics for shade structures and awnings. Face power output is rated at 275 W STC. With reflected or ambient light underneath, the power rating is boosted to 305 W STC. UL certification is pending.

Comments (5)

Darr Hoag's picture

So, this sounds like the tech Solyndra was working on... is this the company that bought Solyndra's assets, or did they pirate the technology, or what?

Ben Root's picture
Bi-Facial modules have been around for more than a decade (Sanyo was an early adopter/experimenter). Not like Solyndra at all.
Michael Welch's picture
Solyndra's technology was different. It's theory was to put solar cells in reflective tubes to capture photons at any angle of sun. Didn't work out to be worth the added cost.

These PV modules, like some other bifacial modules, are flat and can take advantage of some reflected light coming back up from the bottom. There is no opaque backing, but rather two layers of glass with the cells sandwiched. That way the cells can capture some of the light bouncing back from the bottom, making the PV modules more efficient.
Andreas Dutschke's picture

So what happens if you set up mirrors?

Ben Root's picture
The GSX spec sheet shows output for backside irradiance up to +30% (E.G. 332.5 W @ peak power for the GSX265-60M-C module). Pretty nice. Remember though, it would take a lot of mirrors to account for reflection on the modules as the angle of the sun changes throughout the day. Also, you'd have to plan for the increased output on your all your BOS equipment (from inverter sizing, to wire sizing). And then I wonder if, (like historical experiments using concentrating lenses) the cell temp would go up, driving voltage down, and increasing the rate of degradation. Probably better to just appreciate those snow days.
Show or Hide All Comments