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54BGDF-505W vs 54GDF-520W 14 of 19 identical Swap Change panels

GCL NT12R/54BGDF-505W vs GCL NT12R/54GDF-520W

NT12R/54BGDF-505W
505 Wp 22.70 % TOPCon Bifacial
Open panel page Datasheet PDF
VS
NT12R/54GDF-520W
520 Wp 23.37 % TOPCon Bifacial
Open panel page Datasheet PDF
The verdict

54GDF-520W leads on the differences that matter

The largest is module efficiency: 0.67 pp more efficient. 14 of 19 comparable parameters are identical.

See all 5 differences
How alike are they
14 of 19 comparable
parameters are identical
identical differs
01

What actually differs

5 of 19 parameters
Parameter 54BGDF-505W 54GDF-520W Difference
Module efficiency 22.70 % 23.37 % 0.67 pp more efficient
Power density 227.0 Wp/m² 233.7 Wp/m² 6.7 Wp/m² higher
Rated power 505 Wp 520 Wp 15 W more power
Short-circuit current 15.44 A 16.11 A 0.67 A apart
Current at max power 14.76 A 15.30 A 0.54 A apart
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 (-0.290 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
54BGDF-505W
16,944 kWh
54GDF-520W
17,447 kWh
Lifetime gap
503 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario 54BGDF-505W 54GDF-520W
Standard test conditions 25 °C 100.0% of rated power 505 W 520 W
Cool, bright day 40 °C 95.7% of rated power 483 W 497 W
Typical summer roof 55 °C 91.3% of rated power 461 W 475 W
Hot roof 70 °C 87.0% of rated power 439 W 452 W
03

Full specification

Parameter 54BGDF-505W 54GDF-520W Difference
Power and efficiency
Rated power 505 Wp 520 Wp +15 W for 54GDF-520W
Module efficiency 22.70 % 23.37 % +0.67 pp for 54GDF-520W
Power density 227.0 Wp/m² 233.7 Wp/m² +6.7 Wp/m² for 54GDF-520W
Open-circuit voltage 40.61 V 40.05 V Effectively the same
Voltage at max power 34.22 V 33.99 V Effectively the same
Short-circuit current 15.44 A 16.11 A 0.67 A apart
Current at max power 14.76 A 15.30 A 0.54 A apart
Temperature
Temperature coefficient -0.290 %/°C -0.290 %/°C Same
Mechanical
Dimensions 1962x1134x30 mm 1962x1134x30 mm Same
Module area 2.225 m² 2.225 m² Same
Weight 27.3 kg 27.3 kg Same
Weight per kWp 54.1 kg/kWp 52.5 kg/kWp Effectively the same
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.40 %/yr 0.40 %/yr Same
Technology
Cell technology TOPCon TOPCon Same
Cell type Monocrystalline Monocrystalline Same
Cell count 108 108 Same
Bifacial Yes Yes Same
04

Against the whole database

14,005 panels
Efficiency
#3,307 vs #930
54GDF-520W leads by 2,377 places
Power density
#3,353 vs #919
54GDF-520W leads by 2,434 places
Heat behaviour
#2,165 vs #2,165
Tied - the same position in the database
Weight
#8,277 vs #6,043
54GDF-520W leads by 2,234 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#6,858 vs #5,503
54GDF-520W leads by 1,355 places
05

More useful comparisons

Open the full database
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL GCL-NT12R/54GDF-530
6 differences, the largest is module efficiency
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL NT12R/54GDF-525W
6 differences, the largest is module efficiency
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL GCL-NT12R/54GDF-525
6 differences, the largest is module efficiency
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL NT12R/54BGDF-520W
3 differences, the largest is module efficiency
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL GCL-NT12R/54GDF-520
5 differences, the largest is module efficiency
Same series, other bin
GCL NT12R/54BGDF-505W vs GCL NT12R/54BGDF-515W
3 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: GCL NT12R/54BGDF-505W or GCL NT12R/54GDF-520W?
According to our database: GCL NT12R/54GDF-520 W has higher module efficiency (23.37% vs 22.70%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of GCL NT12R/54BGDF-505W and GCL NT12R/54GDF-520W?
GCL NT12R/54BGDF-505 W has a module efficiency of 22.70%, while GCL NT12R/54GDF-520 W is 23.37%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does GCL NT12R/54BGDF-505W use vs GCL NT12R/54GDF-520W?
GCL NT12R/54BGDF-505 W uses TOPCon cells; GCL NT12R/54GDF-520 W uses TOPCon. 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 GCL NT12R/54BGDF-505W and GCL NT12R/54GDF-520W?
GCL NT12R/54BGDF-505 W has a 30 years power warranty; GCL NT12R/54GDF-520 W 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 GCL NT12R/54BGDF-505W and GCL NT12R/54GDF-520W bifacial panels?
Both GCL NT12R/54BGDF-505 W and GCL NT12R/54GDF-520 W 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.

Shop prices: See 6 GCL offers

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.