Renogy 640W (2 x 320W) N-Type 18BB Rigid Solar Panel 2-Pack vs Renogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-Pack

Last updated: October 21, 2026

The Renogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-Pack is the better rigid solar panel overall, rated 4.2 to 4.0. The Renogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-Pack leads on value. The Renogy 640W (2 x 320W) N-Type 18BB Rigid Solar Panel 2-Pack costs $60 less ($599.99 vs $659.99).

Renogy 640W (2 x 320W) N-Type 18BB Rigid Solar Panel 2-Pack vs Renogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-Pack

Prices were last checked October 21, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.

Which should you buy?

Scores side by side

Each factor is scored 0-100 against the same fixed reference points for every 150 w and up rigid solar panel; a clear win is highlighted. How we rank explains each one.

Factor weightRenogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-PackRenogy 640W (2 x 320W) N-Type 18BB Rigid Solar Panel 2-Pack
Overall rating4.2/54.0/5
Value 45%64 $0.82 per rated watt54 $0.94 per rated watt
Tested output 15%50 not yet independently tested (neutral score used)50 not yet independently tested (neutral score used)
Durability 25%100 IP68, 10-year warranty100 IP68, 10-year warranty
Efficiency 15%100 25% claimed efficiency100 25% claimed efficiency

Specifications

Renogy 800W (2 x 400W) N-Type 16BB Bifacial Rigid Solar Panel 2-PackRenogy 640W (2 x 320W) N-Type 18BB Rigid Solar Panel 2-Pack
Output
Rated power800 W640 W
Efficiency25% (cell efficiency, "up to"; datasheet module efficiency 21.5%)25% (cell efficiency, "up to"; datasheet module efficiency 22.2%)
CellsMonocrystalline (N-type, 16BB, half-cut, 108 cells)Monocrystalline (N-type, 18BB (per Renogy's product page and Amazon; the datasheet says only monocrystalline, 60 cells))
BifacialYesNo
Electrical
Open-circuit voltage (Voc)39.4 V43.8 V
Voltage at max power (Vmp)34 V37.9 V
Short-circuit current (Isc)13.1 A8.9 A
Current at max power (Imp)11.8 A8.5 A
Voc temperature coefficient-0.3%/°C-0.3%/°C
Series / parallelYes-
Connections
Output connectorMC4Solar connectors (IP68)
Build
Dimensions67.8 x 44.7 x 1.4 in (each panel)64.6 x 34.7 x 1.4 in (each panel)
Frameanodized aluminum alloyanodized aluminum alloy
Glass3.2 mm tempered3.2 mm tempered
Junction box ratingIP68IP68
Warranty10 years10 years
Output warranty25-year power output warranty95% output for 5 years, 90% for 10 years, 80% for 25 years