Does anyone have any experience with Sunpreme panels?

[max2015]

Does anyone have any experience with Sunpreme?

One of the installers we're considering has specified Sunpreme SNPM-GxB-350 Modules... They will be paired with SolarEdge optimizers...

http://www.sunpreme.com/

We have limited space on our roof and need to maximize output, hence why I'm looking for high wattage modules... 345W SunPower panels just don't make financial sense... Other than the LG Mono X NeON 305W Modules (LG305N1C-B3), any other suggestions?

Thanks!

[DanKegel]

bifacial panels are only a win if back side gets *lots* of light, e.g. tilted panels on a white flat roof.

Those gxb 360s are 6 feet rather than 5 feet long, so the wattage per area isn't as high as you might think.

How many fit on your roof? How many LG 305's fit?
What price per watt before subsidy?
How many kWh/year does pvwatts say they'll generate?
How many kWh/year do you use?

[sensij]

See this thread for more background.

The Sunpreme's have a neat look, and would be my top choice for a "premium" panel, if that is what you are going for. Even though it is a bigger 72 cell panel, 20% efficiency is right up there with the best of them (the LG305's are 18.6%). It would probably be more cost effective to put less expensive panels up and just accept your bill offset will be less than you hoped, but if you are determined to go big, these panels look like a good choice to me.

[DanKegel]

Thanks for linking to the context. I really need to look for that myself next time.

They're only 20% with the backside illuminated, see

http://www.sunpreme.com/wp-content/uploads/2014/12/Sunpreme-Datasheet-GxB-360W-Bifacial-Module-Rev-1.1.pdf

If the roof's not flat and painted white, and the panels aren't mounted on a tilt, they won't get any benefit from their back surface, and they'll be back down to 18%.

[sensij]

Ah, good point. I mixed up the cell efficiency and module efficiency when I looked at it earlier.

[J.P.M.]

Like Dan wrote, if they are parallel with a flat, dark roof, as is common, the back side enhancement is essentially non existent and you wind up with an ~ 18% eff. panel. Not bad, but not worth much of a premium, particularly when you figure the mfg. cost may well drop by the elimination of the back sheet.

One other point: If not parallel and close to a surface, and thus not shading that surface and thereby gaining some output from more input, an energy balance will show that the plate temp. increases in convoluted way and further decreases mod. efficiency.

Double sided panels can make sense, but the way most panels are used - parallel to a dark roof - makes any design advantage close to zero in any meaningful or measureable sense and reduces any such advantage to an advertising gimmick.