Tongwei TWMNH-66HD645 vs Tongwei TWMNF-66HD740
VS
The verdict
7 differences, and they point both ways
The largest is rated power: 95 W more power. 12 of 19 comparable parameters are identical.
See all 7 differencesHow alike are they
12
of 19 comparable
parameters are identical
parameters are identical
identical
differs
01
7 of 19 parameters
What actually differs
Parameter
TWMNH-66HD645
TWMNF-66HD740
Difference
Rated power
645 Wp
740 Wp
95 W more power
Weight
32.2 kg
37.3 kg
5.1 kg lighter
Short-circuit current
16.39 A
18.81 A
2.42 A apart
Module area
2.701 m²
3.106 m²
0.405 m² apart
Cell technology
N-type
TOPCon
N-type vs TOPCon
Current at max power
15.54 A
17.75 A
2.21 A apart
Dimensions
2382x1134x30 mm
2384x1303x33 mm
2382x1134x30 mm vs 2384x1303x33 mm
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 (-0.280 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
TWMNH-66HD645
21,641 kWh
TWMNF-66HD740
24,828 kWh
Lifetime gap
3,187 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario
TWMNH-66HD645
TWMNF-66HD740
Standard test conditions
25 °C
100.0% of rated power
645 W
740 W
Cool, bright day
40 °C
95.8% of rated power
618 W
709 W
Typical summer roof
55 °C
91.6% of rated power
591 W
678 W
Hot roof
70 °C
87.4% of rated power
564 W
647 W
03
Full specification
Parameter
TWMNH-66HD645
TWMNF-66HD740
Difference
Power and efficiency
Rated power
645 Wp
740 Wp
+95 W for TWMNF-66HD740
Module efficiency
23.90 %
23.80 %
Effectively the same
Power density
238.8 Wp/m²
238.2 Wp/m²
Effectively the same
Open-circuit voltage
49.85 V
49.80 V
Effectively the same
Voltage at max power
41.51 V
41.69 V
Effectively the same
Short-circuit current
16.39 A
18.81 A
2.42 A apart
Current at max power
15.54 A
17.75 A
2.21 A apart
Temperature
Temperature coefficient
-0.280 %/°C
-0.280 %/°C
Same
Mechanical
Dimensions
2382x1134x30 mm
2384x1303x33 mm
2382x1134x30 mm vs 2384x1303x33 mm
Module area
2.701 m²
3.106 m²
0.405 m² apart
Weight
32.2 kg
37.3 kg
-5.1 kg for TWMNH-66HD645
Weight per kWp
49.9 kg/kWp
50.4 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
N-type
TOPCon
N-type vs TOPCon
Cell type
Monocrystalline
Monocrystalline
Same
Cell count
132
132
Same
Bifacial
Yes
Yes
Same
04
14,005 panels
Against the whole database
Efficiency
#351
vs
#433
TWMNH-66HD645 leads by 82 places
Power density
#356
vs
#431
TWMNH-66HD645 leads by 75 places
Heat behaviour
#1,309
vs
#1,309
Tied - the same position in the database
Weight
#3,293
vs
#3,784
TWMNH-66HD645 leads by 491 places
Warranty
#21
vs
#21
Tied - the same position in the database
Overall
#1,342
vs
#183
TWMNF-66HD740 leads by 1,159 places
05
Open the full database
More useful comparisons
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Tongwei TWMNH-66HD645 vs Tongwei TWMHF-66HD740X
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Tongwei TWMNH-66HD645 vs Tongwei TWMNF-66HD735
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Tongwei TWMNH-66HD645 vs Tongwei TWMHF-66HD735X
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Tongwei TWMNH-66HD645 vs Tongwei TWMHF-66HD730X
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06
Written summary
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07
Questions about this pairing
Which panel is better: Tongwei TWMNH-66HD645 or Tongwei TWMNF-66HD740?
According to our database: Tongwei TWMNH-66HD645 has higher module efficiency (23.90% vs 23.80%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Tongwei TWMNH-66HD645 and Tongwei TWMNF-66HD740?
Tongwei TWMNH-66HD645 has a module efficiency of 23.90%, while Tongwei TWMNF-66HD740 is 23.80%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Tongwei TWMNH-66HD645 use vs Tongwei TWMNF-66HD740?
Tongwei TWMNH-66HD645 uses N-type cells; Tongwei TWMNF-66HD740 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 Tongwei TWMNH-66HD645 and Tongwei TWMNF-66HD740?
Tongwei TWMNH-66HD645 has a 30 years power warranty; Tongwei TWMNF-66HD740 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 TWMNH-66HD645 and Tongwei TWMNF-66HD740 bifacial panels?
Both Tongwei TWMNH-66HD645 and Tongwei TWMNF-66HD740 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 53 Tongwei 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.

