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HiE-S435HG(FB) vs HiS-T640NJ 1 of 18 identical Swap Change panels

Hyundai HiE-S435HG(FB) vs Hyundai HiS-T640NJ

Hyundai HiE-S435HG(FB)
HiE-S435HG(FB)
435 Wp 20.90 % PERC
Open panel page Datasheet PDF
VS
HiS-T640NJ
640 Wp 22.90 % TOPCon Bifacial
Open panel page Datasheet PDF
The verdict

HiS-T640NJ leads on the differences that matter

The largest is module efficiency: 2.00 pp more efficient. 1 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.

See all 17 differences
How alike are they
1 of 18 comparable
parameters are identical
identical differs not published
01

What actually differs

17 of 18 parameters
Parameter HiE-S435HG(FB) HiS-T640NJ Difference
Module efficiency 20.90 % 22.90 % 2.00 pp more efficient
Temperature coefficient -0.340 %/°C -0.290 %/°C 0.050 %/°C better in heat
Rated power 435 Wp 640 Wp 205 W more power
Power density 209.0 Wp/m² 229.0 Wp/m² 20.0 Wp/m² higher
Performance warranty 25 yrs 30 yrs 5 yrs longer
Annual degradation 0.55 %/yr 0.40 %/yr 0.15 %/yr slower
Weight 21.8 kg 34.7 kg 12.9 kg lighter
Product warranty 25 yrs 12 yrs 13 yrs longer
Open-circuit voltage 43.60 V 57.77 V 14.17 V apart
Module area 2.081 m² 2.795 m² 0.714 m² apart
Weight per kWp 50.1 kg/kWp 54.2 kg/kWp 4.1 kg/kWp lighter
Short-circuit current 12.79 A 14.06 A 1.27 A apart
Cell technology PERC TOPCon PERC vs TOPCon
Voltage at max power 36.20 V 47.74 V 11.54 V apart
Bifacial No Yes No vs Yes
Current at max power 12.02 A 13.41 A 1.39 A apart
Dimensions 1899x1096x30 mm 2465x1134x30 mm 1899x1096x30 mm vs 2465x1134x30 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
HiE-S435HG(FB)
14,098 kWh
HiS-T640NJ
21,473 kWh
Lifetime gap
7,375 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario HiE-S435HG(FB) HiS-T640NJ
Standard test conditions 25 °C 100.0% of rated power 435 W 640 W
Cool, bright day 40 °C 94.9% of rated power 413 W 612 W
Typical summer roof 55 °C 89.8% of rated power 391 W 584 W
Hot roof 70 °C 84.7% of rated power 368 W 556 W
03

Full specification

Parameter HiE-S435HG(FB) HiS-T640NJ Difference
Power and efficiency
Rated power 435 Wp 640 Wp +205 W for HiS-T640NJ
Module efficiency 20.90 % 22.90 % +2.00 pp for HiS-T640NJ
Power density 209.0 Wp/m² 229.0 Wp/m² +20.0 Wp/m² for HiS-T640NJ
Open-circuit voltage 43.60 V 57.77 V 14.17 V apart
Voltage at max power 36.20 V 47.74 V 11.54 V apart
Short-circuit current 12.79 A 14.06 A 1.27 A apart
Current at max power 12.02 A 13.41 A 1.39 A apart
Temperature
Temperature coefficient -0.340 %/°C -0.290 %/°C +0.050 %/°C for HiS-T640NJ
Mechanical
Dimensions 1899x1096x30 mm 2465x1134x30 mm 1899x1096x30 mm vs 2465x1134x30 mm
Module area 2.081 m² 2.795 m² 0.714 m² apart
Weight 21.8 kg 34.7 kg -12.9 kg for HiE-S435HG(FB)
Weight per kWp 50.1 kg/kWp 54.2 kg/kWp -4.1 kg/kWp for HiE-S435HG(FB)
Warranty and degradation
Product warranty 25 yrs 12 yrs +13 yrs for HiE-S435HG(FB)
Performance warranty 25 yrs 30 yrs +5 yrs for HiS-T640NJ
Annual degradation 0.55 %/yr 0.40 %/yr -0.15 %/yr for HiS-T640NJ
Technology
Cell technology PERC TOPCon PERC vs TOPCon
Cell type Monocrystalline Monocrystalline Same
Cell count - 156 Not published by Hyundai
Bifacial No Yes No vs Yes
04

Against the whole database

14,129 panels
Efficiency
#10,148 vs #2,412
HiS-T640NJ leads by 7,736 places
Power density
#10,262 vs #2,443
HiS-T640NJ leads by 7,819 places
Heat behaviour
#8,846 vs #2,220
HiS-T640NJ leads by 6,626 places
Weight
#3,628 vs #8,527
HiE-S435HG(FB) leads by 4,899 places
Warranty
#9,912 vs #21
HiS-T640NJ leads by 9,891 places
Overall
#9,722 vs #2,117
HiS-T640NJ leads by 7,605 places
05

More useful comparisons

Open the full database
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S445HG
3 differences, the largest is module efficiency
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S445HG(FB)
3 differences, the largest is module efficiency
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S440HG
One difference: module efficiency
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S440HG(FB)
One difference: module efficiency
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S435HG
The same specification on paper
Same series, other bin
Hyundai HiE-S435HG(FB) vs Hyundai HiE-S430HG(FB)
One difference: module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: Hyundai HiE-S435HG(FB) or Hyundai HiS-T640NJ?
According to our database: Hyundai HiS-T640NJ has higher module efficiency (22.90% vs 20.90%); Hyundai HiS-T640NJ tolerates heat better (temp coeff -0.290%/°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 Hyundai HiE-S435HG(FB) and Hyundai HiS-T640NJ?
Hyundai HiE-S435HG(FB) has a module efficiency of 20.90%, while Hyundai HiS-T640NJ is 22.90%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Hyundai HiE-S435HG(FB) use vs Hyundai HiS-T640NJ?
Hyundai HiE-S435HG(FB) uses PERC cells; Hyundai HiS-T640NJ 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 Hyundai HiE-S435HG(FB) and Hyundai HiS-T640NJ?
Hyundai HiE-S435HG(FB) has a 25 years power warranty; Hyundai HiS-T640NJ 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 Hyundai HiE-S435HG(FB) and Hyundai HiS-T640NJ bifacial panels?
Hyundai HiS-T640NJ is bifacial (captures light from both faces); Hyundai HiE-S435HG(FB) is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath.

Shop prices: See 30 Hyundai 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.