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JAM72S42-645/LR vs JAM72S40-605/LR 11 of 19 identical Swap Change panels

JA Solar JAM72S42-645/LR vs JA Solar JAM72S40-605/LR

JA Solar JAM72S42-645/LR
JAM72S42-645/LR
645 Wp 23.10 % TOPCon
Open panel page Datasheet PDF
VS
JA Solar JAM72S40-605/LR
JAM72S40-605/LR
605 Wp 22.90 % TOPCon
Open panel page Datasheet PDF
The verdict

8 differences, and they point both ways

The largest is rated power: 40 W more power. 11 of 19 comparable parameters are identical.

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

What actually differs

8 of 19 parameters
Parameter JAM72S42-645/LR JAM72S40-605/LR Difference
Rated power 645 Wp 605 Wp 40 W more power
Weight 29.6 kg 24.3 kg 5.3 kg lighter
Weight per kWp 45.9 kg/kWp 40.2 kg/kWp 5.7 kg/kWp lighter
Module area 2.795 m² 2.646 m² 0.150 m² apart
Module efficiency 23.10 % 22.90 % 0.20 pp more efficient
Short-circuit current 15.36 A 14.53 A 0.83 A apart
Dimensions 2465x1134x30 mm 2333x1134x30 mm 2465x1134x30 mm vs 2333x1134x30 mm
Current at max power 14.50 A 13.77 A 0.73 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
Same temp coeff. for both panels (-0.290 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
JAM72S42-645/LR
21,641 kWh
JAM72S40-605/LR
20,299 kWh
Lifetime gap
1,342 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario JAM72S42-645/LR JAM72S40-605/LR
Standard test conditions 25 °C 100.0% of rated power 645 W 605 W
Cool, bright day 40 °C 95.7% of rated power 617 W 579 W
Typical summer roof 55 °C 91.3% of rated power 589 W 552 W
Hot roof 70 °C 87.0% of rated power 561 W 526 W
03

Full specification

Parameter JAM72S42-645/LR JAM72S40-605/LR Difference
Power and efficiency
Rated power 645 Wp 605 Wp +40 W for JAM72S42-645/LR
Module efficiency 23.10 % 22.90 % +0.20 pp for JAM72S42-645/LR
Power density 230.7 Wp/m² 228.7 Wp/m² Effectively the same
Open-circuit voltage 53.07 V 52.60 V Effectively the same
Voltage at max power 44.49 V 43.94 V Effectively the same
Short-circuit current 15.36 A 14.53 A 0.83 A apart
Current at max power 14.50 A 13.77 A 0.73 A apart
Temperature
Temperature coefficient -0.290 %/°C -0.290 %/°C Same
Mechanical
Dimensions 2465x1134x30 mm 2333x1134x30 mm 2465x1134x30 mm vs 2333x1134x30 mm
Module area 2.795 m² 2.646 m² 0.150 m² apart
Weight 29.6 kg 24.3 kg -5.3 kg for JAM72S40-605/LR
Weight per kWp 45.9 kg/kWp 40.2 kg/kWp -5.7 kg/kWp for JAM72S40-605/LR
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 25 yrs 25 yrs Same
Annual degradation 0.40 %/yr 0.40 %/yr Same
Technology
Cell technology TOPCon TOPCon Same
Cell type Monocrystalline Monocrystalline Same
Cell count 144 144 Same
Bifacial No No Same
04

Against the whole database

14,005 panels
Efficiency
#1,570 vs #2,359
JAM72S42-645/LR leads by 789 places
Power density
#1,654 vs #2,452
JAM72S42-645/LR leads by 798 places
Heat behaviour
#2,165 vs #2,165
Tied - the same position in the database
Weight
#910 vs #160
JAM72S40-605/LR leads by 750 places
Warranty
#9,798 vs #9,798
Tied - the same position in the database
Overall
#2,495 vs #3,932
JAM72S42-645/LR leads by 1,437 places
05

More useful comparisons

Open the full database
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S42-650/LR
One difference: module efficiency
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S42-640/LR
One difference: module efficiency
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S42-635/LR
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S42-630/LR
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S42-625/LR
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S42-645/LR vs JA Solar JAM72S40-600/LR
9 differences, the largest is rated power
06

Written summary

07

Questions about this pairing

Which panel is better: JA Solar JAM72S42-645/LR or JA Solar JAM72S40-605/LR?
According to our database: JA Solar JAM72S42-645/LR has higher module efficiency (23.10% vs 22.90%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of JA Solar JAM72S42-645/LR and JA Solar JAM72S40-605/LR?
JA Solar JAM72S42-645/LR has a module efficiency of 23.10%, while JA Solar JAM72S40-605/LR is 22.90%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM72S42-645/LR use vs JA Solar JAM72S40-605/LR?
JA Solar JAM72S42-645/LR uses TOPCon cells; JA Solar JAM72S40-605/LR 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 JA Solar JAM72S42-645/LR and JA Solar JAM72S40-605/LR?
JA Solar JAM72S42-645/LR has a 25 years power warranty; JA Solar JAM72S40-605/LR 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 386 JA 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.