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STP675S-D66/Wmh vs STP665S-D66/Wmh 16 of 19 identical Swap Change panels

Suntech STP675S-D66/Wmh vs Suntech STP665S-D66/Wmh

Suntech STP675S-D66/Wmh
STP675S-D66/Wmh
675 Wp 21.70 % TOPCon
Open panel page Datasheet PDF
VS
Suntech STP665S-D66/Wmh
STP665S-D66/Wmh
665 Wp 21.40 % TOPCon
Open panel page Datasheet PDF
The verdict

STP675S-D66/Wmh leads on the differences that matter

The largest is module efficiency: 0.30 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 STP675S-D66/Wmh STP665S-D66/Wmh Difference
Module efficiency 21.70 % 21.40 % 0.30 pp more efficient
Power density 217.3 Wp/m² 214.1 Wp/m² 3.2 Wp/m² higher
Rated power 675 Wp 665 Wp 10 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 (-0.340 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
STP675S-D66/Wmh
21,876 kWh
STP665S-D66/Wmh
21,552 kWh
Lifetime gap
324 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario STP675S-D66/Wmh STP665S-D66/Wmh
Standard test conditions 25 °C 100.0% of rated power 675 W 665 W
Cool, bright day 40 °C 94.9% of rated power 641 W 631 W
Typical summer roof 55 °C 89.8% of rated power 606 W 597 W
Hot roof 70 °C 84.7% of rated power 572 W 563 W
03

Full specification

Parameter STP675S-D66/Wmh STP665S-D66/Wmh Difference
Power and efficiency
Rated power 675 Wp 665 Wp +10 W for STP675S-D66/Wmh
Module efficiency 21.70 % 21.40 % +0.30 pp for STP675S-D66/Wmh
Power density 217.3 Wp/m² 214.1 Wp/m² +3.2 Wp/m² for STP675S-D66/Wmh
Open-circuit voltage 46.65 V 46.25 V Effectively the same
Voltage at max power 38.65 V 38.25 V Effectively the same
Short-circuit current 18.47 A 18.39 A Effectively the same
Current at max power 17.46 A 17.39 A Effectively the same
Temperature
Temperature coefficient -0.340 %/°C -0.340 %/°C Same
Mechanical
Dimensions 2384x1303x35 mm 2384x1303x35 mm Same
Module area 3.106 m² 3.106 m² Same
Weight 33.5 kg 33.5 kg Same
Weight per kWp 49.6 kg/kWp 50.4 kg/kWp Effectively the same
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 25 yrs 25 yrs Same
Annual degradation 0.55 %/yr 0.55 %/yr Same
Technology
Cell technology TOPCon TOPCon Same
Cell type Monocrystalline Monocrystalline Same
Cell count 132 132 Same
Bifacial No No Same
04

Against the whole database

14,005 panels
Efficiency
#7,421 vs #8,323
STP675S-D66/Wmh leads by 902 places
Power density
#7,349 vs #8,250
STP675S-D66/Wmh leads by 901 places
Heat behaviour
#8,778 vs #8,778
Tied - the same position in the database
Weight
#3,176 vs #3,742
STP675S-D66/Wmh leads by 566 places
Warranty
#9,798 vs #9,798
Tied - the same position in the database
Overall
#3,026 vs #3,792
STP675S-D66/Wmh leads by 766 places
05

More useful comparisons

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06

Written summary

07

Questions about this pairing

Which panel is better: Suntech STP675S-D66/Wmh or Suntech STP665S-D66/Wmh?
According to our database: Suntech STP675S-D66/Wmh has higher module efficiency (21.70% vs 21.40%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Suntech STP675S-D66/Wmh and Suntech STP665S-D66/Wmh?
Suntech STP675S-D66/Wmh has a module efficiency of 21.70%, while Suntech STP665S-D66/Wmh is 21.40%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Suntech STP675S-D66/Wmh use vs Suntech STP665S-D66/Wmh?
Suntech STP675S-D66/Wmh uses TOPCon cells; Suntech STP665S-D66/Wmh 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 Suntech STP675S-D66/Wmh and Suntech STP665S-D66/Wmh?
Suntech STP675S-D66/Wmh has a 25 years power warranty; Suntech STP665S-D66/Wmh has a 25 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.

Shop prices: See 22 Suntech 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.