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66HD715X vs 66HD740X 16 of 19 identical Swap Change panels

Tongwei TWMHF-66HD715X vs Tongwei TWMHF-66HD740X

TWMHF-66HD715X
715 Wp 23.00 % N-type Bifacial
Open panel page Datasheet PDF
VS
TWMHF-66HD740X
740 Wp 23.80 % N-type Bifacial
Open panel page Datasheet PDF
The verdict

66HD740X leads on the differences that matter

The largest is module efficiency: 0.80 pp more efficient. 16 of 19 comparable parameters are identical.

See all 3 differences
How alike are they
16 of 19 comparable
parameters are identical
identical differs
01

What actually differs

3 of 19 parameters
Parameter 66HD715X 66HD740X Difference
Module efficiency 23.00 % 23.80 % 0.80 pp more efficient
Power density 230.2 Wp/m² 238.2 Wp/m² 8.0 Wp/m² higher
Rated power 715 Wp 740 Wp 25 W more power
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 (-0.240 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
66HD715X
24,083 kWh
66HD740X
24,925 kWh
Lifetime gap
842 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario 66HD715X 66HD740X
Standard test conditions 25 °C 100.0% of rated power 715 W 740 W
Cool, bright day 40 °C 96.4% of rated power 689 W 713 W
Typical summer roof 55 °C 92.8% of rated power 664 W 687 W
Hot roof 70 °C 89.2% of rated power 638 W 660 W
03

Full specification

Parameter 66HD715X 66HD740X Difference
Power and efficiency
Rated power 715 Wp 740 Wp +25 W for 66HD740X
Module efficiency 23.00 % 23.80 % +0.80 pp for 66HD740X
Power density 230.2 Wp/m² 238.2 Wp/m² +8.0 Wp/m² for 66HD740X
Open-circuit voltage 50.22 V 50.62 V Effectively the same
Voltage at max power 41.84 V 42.32 V Effectively the same
Short-circuit current 17.98 A 18.47 A Effectively the same
Current at max power 17.09 A 17.49 A Effectively the same
Temperature
Temperature coefficient -0.240 %/°C -0.240 %/°C Same
Mechanical
Dimensions 2384x1303x33 mm 2384x1303x33 mm Same
Module area 3.106 m² 3.106 m² Same
Weight 37.0 kg 37.0 kg Same
Weight per kWp 51.7 kg/kWp 50.0 kg/kWp Effectively the same
Warranty and degradation
Product warranty 15 yrs 15 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.38 %/yr 0.38 %/yr Same
Technology
Cell technology N-type N-type Same
Cell type Monocrystalline Monocrystalline Same
Cell count 132 132 Same
Bifacial Yes Yes Same
04

Against the whole database

14,005 panels
Efficiency
#1,919 vs #433
66HD740X leads by 1,486 places
Power density
#2,018 vs #431
66HD740X leads by 1,587 places
Heat behaviour
#13 vs #13
Tied - the same position in the database
Weight
#5,113 vs #3,317
66HD740X leads by 1,796 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#443 vs #130
66HD740X leads by 313 places
05

More useful comparisons

Open the full database
Same series, other bin
Tongwei TWMHF-66HD715X vs Tongwei TWMHF-66HD735X
3 differences, the largest is module efficiency
Same series, other bin
Tongwei TWMHF-66HD715X vs Tongwei TWMHF-66HD730X
3 differences, the largest is module efficiency
Same series, other bin
Tongwei TWMHF-66HD715X vs Tongwei TWMHF-66HD725X
3 differences, the largest is module efficiency
Same series, other bin
Tongwei TWMHF-66HD715X vs Tongwei TWMHF-66HD720X
One difference: module efficiency
Same manufacturer
Tongwei TWMHF-66HD715X vs Tongwei TWMNF-66HD750
9 differences, the largest is module efficiency
Same manufacturer
Tongwei TWMHF-66HD715X vs Tongwei TWMNF-66HD745
8 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: Tongwei TWMHF-66HD715X or Tongwei TWMHF-66HD740X?
According to our database: Tongwei TWMHF-66HD740X has higher module efficiency (23.80% vs 23.00%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Tongwei TWMHF-66HD715X and Tongwei TWMHF-66HD740X?
Tongwei TWMHF-66HD715X has a module efficiency of 23.00%, while Tongwei TWMHF-66HD740X is 23.80%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Tongwei TWMHF-66HD715X use vs Tongwei TWMHF-66HD740X?
Tongwei TWMHF-66HD715X uses N-type cells; Tongwei TWMHF-66HD740X uses N-type. 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 Tongwei TWMHF-66HD715X and Tongwei TWMHF-66HD740X?
Tongwei TWMHF-66HD715X has a 30 years power warranty; Tongwei TWMHF-66HD740X 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 Tongwei TWMHF-66HD715X and Tongwei TWMHF-66HD740X bifacial panels?
Both Tongwei TWMHF-66HD715X and Tongwei TWMHF-66HD740X 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.