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DEG21C.20-645 vs NEG21C.20Q-755 8 of 19 identical Swap Change panels

Trina Solar TSM-DEG21C.20-645 vs Trina Solar TSM-NEG21C.20Q-755

Trina Solar TSM-DEG21C.20-645
TSM-DEG21C.20-645
645 Wp 20.80 % PERC Bifacial
Open panel page Datasheet PDF
VS
Trina Solar TSM-NEG21C.20Q-755
TSM-NEG21C.20Q-755
755 Wp 24.30 % TOPCon Bifacial
Open panel page Datasheet PDF
The verdict

NEG21C.20Q-755 leads on the differences that matter

The largest is module efficiency: 3.50 pp more efficient. 8 of 19 comparable parameters are identical.

See all 11 differences
How alike are they
8 of 19 comparable
parameters are identical
identical differs
01

What actually differs

11 of 19 parameters
Parameter DEG21C.20-645 NEG21C.20Q-755 Difference
Module efficiency 20.80 % 24.30 % 3.50 pp more efficient
Temperature coefficient -0.340 %/°C -0.260 %/°C 0.080 %/°C better in heat
Rated power 645 Wp 755 Wp 110 W more power
Power density 207.6 Wp/m² 243.1 Wp/m² 35.4 Wp/m² higher
Weight per kWp 59.4 kg/kWp 50.7 kg/kWp 8.7 kg/kWp lighter
Annual degradation 0.45 %/yr 0.35 %/yr 0.10 %/yr slower
Open-circuit voltage 45.30 V 50.70 V 5.40 V apart
Cell technology PERC TOPCon PERC vs TOPCon
Voltage at max power 37.50 V 42.70 V 5.20 V apart
Cell count 132 264 132 cells apart
Short-circuit current 18.31 A 18.81 A 0.50 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
DEG21C.20-645
21,240 kWh
NEG21C.20Q-755
25,529 kWh
Lifetime gap
4,289 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario DEG21C.20-645 NEG21C.20Q-755
Standard test conditions 25 °C 100.0% of rated power 645 W 755 W
Cool, bright day 40 °C 94.9% of rated power 612 W 726 W
Typical summer roof 55 °C 89.8% of rated power 579 W 696 W
Hot roof 70 °C 84.7% of rated power 546 W 667 W
03

Full specification

Parameter DEG21C.20-645 NEG21C.20Q-755 Difference
Power and efficiency
Rated power 645 Wp 755 Wp +110 W for NEG21C.20Q-755
Module efficiency 20.80 % 24.30 % +3.50 pp for NEG21C.20Q-755
Power density 207.6 Wp/m² 243.1 Wp/m² +35.4 Wp/m² for NEG21C.20Q-755
Open-circuit voltage 45.30 V 50.70 V 5.40 V apart
Voltage at max power 37.50 V 42.70 V 5.20 V apart
Short-circuit current 18.31 A 18.81 A 0.50 A apart
Current at max power 17.23 A 17.69 A Effectively the same
Temperature
Temperature coefficient -0.340 %/°C -0.260 %/°C +0.080 %/°C for NEG21C.20Q-755
Mechanical
Dimensions 2384x1303x33 mm 2384x1303x33 mm Same
Module area 3.106 m² 3.106 m² Same
Weight 38.3 kg 38.3 kg Same
Weight per kWp 59.4 kg/kWp 50.7 kg/kWp -8.7 kg/kWp for NEG21C.20Q-755
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.45 %/yr 0.35 %/yr -0.10 %/yr for NEG21C.20Q-755
Technology
Cell technology PERC TOPCon PERC vs TOPCon
Cell type Monocrystalline Monocrystalline Same
Cell count 132 264 132 cells apart
Bifacial Yes Yes Same
04

Against the whole database

14,005 panels
Efficiency
#10,457 vs #131
NEG21C.20Q-755 leads by 10,326 places
Power density
#10,562 vs #136
NEG21C.20Q-755 leads by 10,426 places
Heat behaviour
#8,778 vs #511
NEG21C.20Q-755 leads by 8,267 places
Weight
#12,126 vs #4,131
NEG21C.20Q-755 leads by 7,995 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#4,248 vs #91
NEG21C.20Q-755 leads by 4,157 places
05

More useful comparisons

Open the full database
Same series, other bin
Trina Solar TSM-DEG21C.20-645 vs Trina Solar TSM-DEG21C.20-665
3 differences, the largest is module efficiency
Same series, other bin
Trina Solar TSM-DEG21C.20-645 vs Trina Solar TSM-DEG21C.20-660
3 differences, the largest is module efficiency
Same series, other bin
Trina Solar TSM-DEG21C.20-645 vs Trina Solar TSM-DEG21C.20-655
3 differences, the largest is module efficiency
Same series, other bin
Trina Solar TSM-DEG21C.20-645 vs Trina Solar TSM-DEG21C.20-650
The same specification on paper
Same series, other bin
Trina Solar TSM-NEG21C.20Q-755 vs Trina Solar TSM-NEG21C.20Q-760
One difference: module efficiency
Same series, other bin
Trina Solar TSM-NEG21C.20Q-755 vs Trina Solar TSM-NEG21C.20Q-750
One difference: module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: Trina Solar TSM-DEG21C.20-645 or Trina Solar TSM-NEG21C.20Q-755?
According to our database: Trina Solar TSM-NEG21C.20Q-755 has higher module efficiency (24.30% vs 20.80%); Trina Solar TSM-NEG21C.20Q-755 tolerates heat better (temp coeff -0.260%/°C vs -0.340%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Trina Solar TSM-DEG21C.20-645 and Trina Solar TSM-NEG21C.20Q-755?
Trina Solar TSM-DEG21C.20-645 has a module efficiency of 20.80%, while Trina Solar TSM-NEG21C.20Q-755 is 24.30%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Trina Solar TSM-DEG21C.20-645 use vs Trina Solar TSM-NEG21C.20Q-755?
Trina Solar TSM-DEG21C.20-645 uses PERC cells; Trina Solar TSM-NEG21C.20Q-755 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 Trina Solar TSM-DEG21C.20-645 and Trina Solar TSM-NEG21C.20Q-755?
Trina Solar TSM-DEG21C.20-645 has a 30 years power warranty; Trina Solar TSM-NEG21C.20Q-755 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 Trina Solar TSM-DEG21C.20-645 and Trina Solar TSM-NEG21C.20Q-755 bifacial panels?
Both Trina Solar TSM-DEG21C.20-645 and Trina Solar TSM-NEG21C.20Q-755 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 213 Trina Solar 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.