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66GDF-730 vs 66GDF 720 15 of 18 identical Swap Change panels

GCL GCL-NT12/66GDF-730 vs GCL GCL-NT12/66GDF 720

GCL GCL-NT12/66GDF-730
GCL-NT12/66GDF-730
730 Wp 23.50 % TOPCon Bifacial
Open panel page Datasheet PDF
VS
GCL-NT12/66GDF 720
720 Wp 23.18 % TOPCon Bifacial Incomplete
Open panel page Datasheet PDF
The verdict

66GDF-730 leads on the differences that matter

The largest is module efficiency: 0.32 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 differences
How alike are they
15 of 18 comparable
parameters are identical
identical differs not published
01

What actually differs

3 of 18 parameters
Parameter 66GDF-730 66GDF 720 Difference
Module efficiency 23.50 % 23.18 % 0.32 pp more efficient
Power density 235.0 Wp/m² 231.8 Wp/m² 3.2 Wp/m² higher
Rated power 730 Wp 720 Wp 10 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-730
24,493 kWh
66GDF 720
24,157 kWh
Lifetime gap
336 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario 66GDF-730 66GDF 720
Standard test conditions 25 °C 100.0% of rated power 730 W 720 W
Cool, bright day 40 °C 95.7% of rated power 698 W 689 W
Typical summer roof 55 °C 91.3% of rated power 666 W 657 W
Hot roof 70 °C 87.0% of rated power 635 W 626 W
03

Full specification

Parameter 66GDF-730 66GDF 720 Difference
Power and efficiency
Rated power 730 Wp 720 Wp +10 W for 66GDF-730
Module efficiency 23.50 % 23.18 % +0.32 pp for 66GDF-730
Power density 235.0 Wp/m² 231.8 Wp/m² +3.2 Wp/m² for 66GDF-730
Open-circuit voltage 49.02 V 48.58 V Effectively the same
Voltage at max power 41.22 V 40.84 V Effectively the same
Short-circuit current 18.64 A 18.55 A Effectively the same
Current at max power 17.71 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 52.3 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

Against the whole database

14,005 panels
Efficiency
#716 vs #1,424
66GDF-730 leads by 708 places
Power density
#800 vs #1,347
66GDF-730 leads by 547 places
Heat behaviour
#2,165 vs #2,165
Tied - the same position in the database
Weight
#5,805 vs #7,025
66GDF-730 leads by 1,220 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#312 vs #540
66GDF-730 leads by 228 places
05

More useful comparisons

Open the full database
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL GCL-NT12/66GDF-740
3 differences, the largest is module efficiency
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL GCL-NT12/66GDF-735
The same specification on paper
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL NT12/66GDF-730
The same specification on paper
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL GCL-NT12/66GDF-725
The same specification on paper
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL NT12/66GDF-725
The same specification on paper
Same series, other bin
GCL GCL-NT12/66GDF-730 vs GCL GCL-NT12/66GDF 725
The same specification on paper
06

Written summary

07

Questions about this pairing

Which panel is better: GCL GCL-NT12/66GDF-730 or GCL GCL-NT12/66GDF 720?
According to our database: GCL GCL-NT12/66GDF-730 has higher module efficiency (23.50% 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-730 and GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-730 has a module efficiency of 23.50%, 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-730 use vs GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-730 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-730 and GCL GCL-NT12/66GDF 720?
GCL GCL-NT12/66GDF-730 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-730 and GCL GCL-NT12/66GDF 720 bifacial panels?
Both GCL GCL-NT12/66GDF-730 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.

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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.