GCL GCL-NT12/66GDF-740 vs GCL GCL-NT12/66GDF 720
VS
The verdict
66GDF-740 leads on the differences that matter
The largest is module efficiency: 0.64 pp more efficient. 15 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.
See all 3 differencesHow alike are they
15
of 18 comparable
parameters are identical
parameters are identical
identical
differs
not published
01
3 of 18 parameters
What actually differs
Parameter
66GDF-740
66GDF 720
Difference
Module efficiency
23.82 %
23.18 %
0.64 pp more efficient
Power density
238.2 Wp/m²
231.8 Wp/m²
6.4 Wp/m² higher
Rated power
740 Wp
720 Wp
20 W more power
02
What it means on a roof
Thirty years of production
A 1.0% first-year loss then 0.40% a year, assumed for both panels, 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.
66GDF-740
24,828 kWh
66GDF 720
24,157 kWh
Lifetime gap
671 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario
66GDF-740
66GDF 720
Standard test conditions
25 °C
100.0% of rated power
740 W
720 W
Cool, bright day
40 °C
95.7% of rated power
708 W
689 W
Typical summer roof
55 °C
91.3% of rated power
676 W
657 W
Hot roof
70 °C
87.0% of rated power
643 W
626 W
03
Full specification
Parameter
66GDF-740
66GDF 720
Difference
Power and efficiency
Rated power
740 Wp
720 Wp
+20 W for 66GDF-740
Module efficiency
23.82 %
23.18 %
+0.64 pp for 66GDF-740
Power density
238.2 Wp/m²
231.8 Wp/m²
+6.4 Wp/m² for 66GDF-740
Open-circuit voltage
49.46 V
48.58 V
Effectively the same
Voltage at max power
41.60 V
40.84 V
Effectively the same
Short-circuit current
18.72 A
18.55 A
Effectively the same
Current at max power
17.79 A
17.63 A
Effectively the same
Temperature
Temperature coefficient
-0.290 %/°C
-0.290 %/°C
Same
Mechanical
Dimensions
2384x1303x33 mm
2384x1303x33 mm
Same
Module area
3.106 m²
3.106 m²
Same
Weight
38.2 kg
38.3 kg
Effectively the same
Weight per kWp
51.6 kg/kWp
53.2 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
-
Not published by GCL
Technology
Cell technology
TOPCon
TOPCon
Same
Cell type
Monocrystalline
Monocrystalline
Same
Cell count
132
132
Same
Bifacial
Yes
Yes
Same
04
14,005 panels
Against the whole database
Efficiency
#418
vs
#1,424
66GDF-740 leads by 1,006 places
Power density
#431
vs
#1,347
66GDF-740 leads by 916 places
Heat behaviour
#2,165
vs
#2,165
Tied - the same position in the database
Weight
#4,997
vs
#7,025
66GDF-740 leads by 2,028 places
Warranty
#21
vs
#21
Tied - the same position in the database
Overall
#181
vs
#540
66GDF-740 leads by 359 places
05
Open the full database
More useful comparisons
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL GCL-NT12/66GDF-735
The same specification on paper
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL GCL-NT12/66GDF-730
3 differences, the largest is module efficiency
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL NT12/66GDF-730
3 differences, the largest is module efficiency
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL GCL-NT12/66GDF-725
3 differences, the largest is module efficiency
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL NT12/66GDF-725
3 differences, the largest is module efficiency
Same series, other bin
GCL GCL-NT12/66GDF-740 vs GCL GCL-NT12/66GDF 725
3 differences, the largest is module efficiency
06
Written summary
Checking cache...
07
Questions about this pairing
Which panel is better: GCL GCL-NT12/66GDF-740 or GCL GCL-NT12/66GDF 720?
According to our database: GCL GCL-NT12/66GDF-740 has higher module efficiency (23.82% vs 23.18%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of GCL GCL-NT12/66GDF-740 and GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-740 has a module efficiency of 23.82%, while GCL GCL-NT12/66GDF 720 is 23.18%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does GCL GCL-NT12/66GDF-740 use vs GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-740 uses TOPCon cells; GCL GCL-NT12/66GDF 720 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 GCL-NT12/66GDF-740 and GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-740 has a 30 years power warranty; GCL GCL-NT12/66GDF 720 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 GCL-NT12/66GDF-740 and GCL GCL-NT12/66GDF 720 bifacial panels?
Both GCL GCL-NT12/66GDF-740 and GCL GCL-NT12/66GDF 720 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.