A low-cost bifacial pair for a ground mount or shed roof over light gravel or concrete, where the back side can earn its keep. On a dark roof, Renogy’s N-type 320 W pair is the better panel.
Price checked October 26, 2026. As an Amazon Associate we earn from qualifying purchases.
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
| Output | |
|---|---|
| Rated power | 640 W |
| Module efficiency | 19.2% |
| Claimed efficiency | 19.2% (module efficiency from the datasheet; no cell efficiency published) |
| Cells | Monocrystalline (PERC, 10BB, half-cut, 90 cells (per the Amazon listing and datasheet)) |
| Bifacial | Yes |
| Electrical | |
| Open-circuit voltage (Voc) | 30.4 V |
| Voltage at max power (Vmp) | 26.1 V |
| Short-circuit current (Isc) | 13.1 A |
| Current at max power (Imp) | 12.3 A |
| Voc temperature coefficient | -0.3%/°C |
| Series / parallel | Yes |
| Connections | |
| Output connector | Solar connectors (IP68) |
| Build | |
| Dimensions | 67.9 x 38.0 x 1.4 in (each panel) |
| Frame | anodized aluminum alloy |
| Glass | 3.2 mm tempered |
| Junction box rating | IP68 |
| Warranty | 10 years |
| Output warranty | 25-year power output warranty |
| Released | 2025-07 |
A strong value for a 400 W ground mount, shed roof or large RV roof, and a good match for power stations with a 60 V solar input. Mostly sold as a pair on Amazon.
Amazon $319.99A pair of large N-type bifacial panels for a small home backup, shed or ground-mount system with an MPPT controller. Bigger arrays are cheaper per watt in SUNGOLDPOWER’s larger packs.
Amazon $889A low-cost large bifacial panel for a home rooftop, shed or ground-mount array on a 24 V or 48 V system with an MPPT controller. The thin paperwork and unstated warranty make it a price play rather than a long-term pick.
Amazon $269.99Compare the Renogy 640W (2 x 320W) Bifacial 2-Pack with any other rigid solar panel →
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