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XL-G11S.3 / BFG 605 vs RSF XL-G11S.3 / BFG 585 13 of 18 identical Swap Change panels

Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585

Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605
Q.PEAK DUO XL-G11S.3 / BFG 605
605 Wp 21.70 % PERC Bifacial
Open panel page Datasheet PDF
VS
Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585
Q.PEAK DUO RSF XL-G11S.3 / BFG 585
585 Wp 21.00 % PERC Bifacial
Open panel page Datasheet PDF
The verdict

XL-G11S.3 / BFG 605 leads on the differences that matter

The largest is module efficiency: 0.70 pp more efficient. 13 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.

See all 5 differences
How alike are they
13 of 18 comparable
parameters are identical
identical differs not published
01

What actually differs

5 of 18 parameters
Parameter XL-G11S.3 / BFG 605 RSF XL-G11S.3 / BFG 585 Difference
Module efficiency 21.70 % 21.00 % 0.70 pp more efficient
Power density 216.7 Wp/m² 209.5 Wp/m² 7.2 Wp/m² higher
Rated power 605 Wp 585 Wp 20 W more power
Weight per kWp 57.7 kg/kWp 62.2 kg/kWp 4.5 kg/kWp lighter
Weight 34.9 kg 36.4 kg 1.5 kg lighter
02

What it means on a roof

Thirty years of production
Each panel's own declared degradation curve, at 1,200 kWh/kWp a year
Same temp coeff. for both panels (-0.340 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
XL-G11S.3 / BFG 605
19,923 kWh
RSF XL-G11S.3 / BFG 585
19,265 kWh
Lifetime gap
658 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario XL-G11S.3 / BFG 605 RSF XL-G11S.3 / BFG 585
Standard test conditions 25 °C 100.0% of rated power 605 W 585 W
Cool, bright day 40 °C 94.9% of rated power 574 W 555 W
Typical summer roof 55 °C 89.8% of rated power 543 W 525 W
Hot roof 70 °C 84.7% of rated power 512 W 495 W
03

Full specification

Parameter XL-G11S.3 / BFG 605 RSF XL-G11S.3 / BFG 585 Difference
Power and efficiency
Rated power 605 Wp 585 Wp +20 W for XL-G11S.3 / BFG 605
Module efficiency 21.70 % 21.00 % +0.70 pp for XL-G11S.3 / BFG 605
Power density 216.7 Wp/m² 209.5 Wp/m² +7.2 Wp/m² for XL-G11S.3 / BFG 605
Open-circuit voltage 53.69 V 53.57 V Effectively the same
Voltage at max power 45.40 V 44.75 V Effectively the same
Short-circuit current 13.90 A 13.72 A Effectively the same
Current at max power 13.33 A 13.07 A Effectively the same
Temperature
Temperature coefficient -0.340 %/°C -0.340 %/°C Same
Mechanical
Dimensions 2462x1134x35 mm 2462x1134x35 mm Same
Module area 2.792 m² 2.792 m² Same
Weight 34.9 kg 36.4 kg -1.5 kg for XL-G11S.3 / BFG 605
Weight per kWp 57.7 kg/kWp 62.2 kg/kWp -4.5 kg/kWp for XL-G11S.3 / BFG 605
Warranty and degradation
Product warranty 12 yrs - Not published by Q-Cells
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.45 %/yr 0.45 %/yr Same
Technology
Cell technology PERC PERC Same
Cell type Monocrystalline Monocrystalline Same
Cell count 156 156 Same
Bifacial Yes Yes Same
04

Against the whole database

14,005 panels
Efficiency
#7,421 vs #9,758
XL-G11S.3 / BFG 605 leads by 2,337 places
Power density
#7,537 vs #9,941
XL-G11S.3 / BFG 605 leads by 2,404 places
Heat behaviour
#8,778 vs #8,778
Tied - the same position in the database
Weight
#11,362 vs #12,754
XL-G11S.3 / BFG 605 leads by 1,392 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#4,578 vs #8,794
XL-G11S.3 / BFG 605 leads by 4,216 places
05

More useful comparisons

Open the full database
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 600
3 differences, the largest is module efficiency
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 600
One difference: module efficiency
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 595
5 differences, the largest is module efficiency
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 595
3 differences, the largest is module efficiency
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590
5 differences, the largest is module efficiency
Same series, other bin
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 vs Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 590
3 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 or Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585?
According to our database: Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 has higher module efficiency (21.70% vs 21.00%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585?
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 has a module efficiency of 21.70%, while Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 is 21.00%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 use vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585?
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 uses PERC cells; Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 uses PERC. Modern n-type technologies (TOPCon, HJT, BC) typically deliver higher efficiency and lower degradation compared to older PERC (p-type) cells.
What is the warranty on Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585?
Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 has a 30 years power warranty; Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 has a 30 years power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80-87%). Product (materials) warranties are usually shorter.
Are Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 bifacial panels?
Both Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 are bifacial - they capture reflected light from the ground, which can add 5-15% more annual energy on ground-mount or elevated rooftop installations with a light surface beneath.

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Every figure here is from the manufacturers' own datasheets - a dash means the value is not published, never an estimate. The thirty-year projection and the temperature scenarios are calculations from those figures, and each states its assumption above.